How different online recruitment methods impact on recruitment rates for the web-based coortesnaweb project: a randomised trial.

BACKGROUND: The number of web-based E-epidemiologic studies using online recruitment methods is increasing. However, the optimal online recruitment method in terms of maximizing recruitment rates is still unknown. Our aim was to compare the recruitment rates of three online recruitment methods and to describe how these rates differ according to individual's socioeconomic and demographic factors. METHODS: A total of 2394 members of the 1993 Pelotas birth cohort that provided an e-mail address, a Facebook name, and a WhatsApp number during a face-to-face follow-up were randomly allocated to be recruited by e-mail, Facebook or WhatsApp (798 individuals per method). This was a parallel randomised trial applying a block randomisation (block size = 3). Between January and February 2018, we sent messages inviting them to register into the web-based coortesnaweb platform. Recruitment rates were calculated for each method, and stratified according to the individual's socioeconomic and demographic characteristics. We also analysed absolute and relative inequalities on recruitment according to schooling and socioeconomic position. RESULTS: Out of the 2394 individuals analysed, 642 registered into the platform. The overall recruitment rate was 26.8%. Recruitment rates for women were almost 10 percentage points higher compared to men. Facebook was the most effective recruitment method, as 30.6% of those invited through the social network were recruited. Recruitment rates of e-mail and WhatsApp were similar (recruitment rate = 24.9%). E-mail and Facebook were the most effective recruitment methods to invite highly educated and wealthier individuals. However, sending e-mails to recruit individuals also reflected in the highest inequalities according to schooling and socioeconomic position. In contrast, the lowest inequalities according to socioeconomic position were observed using Facebook. CONCLUSIONS: Facebook was the most effective online recruitment method, also achieving the most equitable sample in terms of schooling and socioeconomic position. The effectiveness of online recruitment methods depends on the characteristics of the sample. It is important to know the profile of the target sample in order to decide which online recruitment method to use. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials, identifier: RBR-3dv7gc , retrospectively registered in 10 April 2018.

Response rate differences between web and alternative data collection methods for public health research: a systematic review of the literature.

OBJECTIVES: To systematically review the literature and compare response rates (RRs) of web surveys to alternative data collection methods in the context of epidemiologic and public health studies. METHODS: We reviewed the literature using PubMed, LILACS, SciELO, WebSM, and Google Scholar databases. We selected epidemiologic and public health studies that considered the general population and used two parallel data collection methods, being one web-based. RR differences were analyzed using two-sample test of proportions, and pooled using random effects. We investigated agreement using Bland-and-Altman, and correlation using Pearson's coefficient. RESULTS: We selected 19 studies (nine randomized trials). The RR of the web-based data collection was 12.9 percentage points (p.p.) lower (95% CI = - 19.0, - 6.8) than the alternative methods, and 15.7 p.p. lower (95% CI = - 24.2, - 7.3) considering only randomized trials. Monetary incentives did not reduce the RR differences. A strong positive correlation (r = 0.83) between the RRs was observed. CONCLUSIONS: Web-based data collection present lower RRs compared to alternative methods. However, it is not recommended to interpret this as a meta-analytical evidence due to the high heterogeneity of the studies.

The effects of using answer sheets on reported drug use and data quality in a classroom survey: A cluster-randomized study.

BACKGROUND: We compare self-reported prevalence of drug use and indicators of data quality from two different response modes (with and without an independent answer sheet for recording responses) in a survey conducted in 2015 among secondary school students. METHODS: Stratified cluster-randomized study conducted among students in grades 8-12 from public, private and subsidized schools in Chile (N=2317 students in 122 classes). Measurements included were: percentage reporting substance use (tobacco, alcohol, marijuana, cocaine, ecstasy); number of inconsistent responses; number of item nonresponses; percentage of extreme reports of drug use; percentage reporting using the nonexistent drug, relevón; and completion times. RESULTS: Compared with those who responded directly in the questionnaire booklet, students who used a separate answer sheet took 17.6 more minutes (95% confidence interval [CI]: 14.4-20.8) to complete the survey and had on average 1.5 more inconsistent responses (95%CI: 0.91-2.14). The prevalence and variance of drug use was higher among those who used an answer sheet for all substances except tobacco; the prevalence ratio (PR) of reported substance use for low-prevalence substances during the past year were: cocaine PR=2.5 (95%CI: 1.6-4.1); ecstasy PR=5.0 (95%CI: 2.4-10.5); relevón PR=4.8 (95%CI: 2.5-9.3). CONCLUSIONS: Using an answer sheet for a self-administered paper-and-pencil survey of drug use among students result in lower quality data and higher reports of drug use. International comparison of adolescent drug use from school-based surveys should be done with caution. The relative ranking of a country could be misleading if different mode of recording answers are used.

The Migrant Border Crossing Study: A methodological overview of research along the Sonora-Arizona border.

Increased border enforcement efforts have redistributed unauthorized Mexican migration to the United States (US) away from traditional points of crossing, such as San Diego and El Paso, and into more remote areas along the US-Mexico border, including southern Arizona. Yet relatively little quantitative scholarly work exists examining Mexican migrants' crossing, apprehension, and repatriation experiences in southern Arizona. We contend that if scholars truly want to understand the experiences of unauthorized migrants in transit, such migrants should be interviewed either at the border after being removed from the US, or during their trajectories across the border, or both. This paper provides a methodological overview of the Migrant Border Crossing Study (MBCS), a unique data source on Mexican migrants who attempted an unauthorized crossing along the Sonora-Arizona border, were apprehended, and repatriated to Nogales, Sonora in 2007-09. We also discuss substantive and theoretical contributions of the MBCS.

Postpartum Women's Perspectives on the Donation of Placentas for Scientific Research in Campinas, Brazil.

Little is known about public perspectives of scientific and therapeutic uses of placentas. Gaps in knowledge potentiate ethical and clinical problems regarding collection and applications. As such, this study sought to assess the perspectives of placenta donation of a sample of women. Postpartum women's perspectives on placental donation were assessed at the State University of Campinas in the Centro de Atençäo Integral a Saúde da Mulher (CAISM) maternity hospital using a cross-sectional survey (n = 384) and semi-structured interviews (n = 12). Surveys were analyzed quantitatively and interviews were analyzed qualitatively using grounded coding; results were compared. The average age of respondents was 27. Fifty-six percent had more than one child, 45% were Caucasian, 38% were mixed-race, 74% identified with a Christian faith, 52% had high school education or higher, 13% regarded the placenta as spiritually important, 72% felt that knowing what happens to the placenta after birth was somewhat or very important, 78% supported the use of the placenta in research and medicine, 59% reported that consent to collect the placenta was very or somewhat important, 78% preferred their doctor to invite donation, and only 7% preferred the researcher to invite donation. Interviews suggested women appreciate being part of research and that receiving information about studies was important to them. Informed by these results, we argue that women support scientific and therapeutic uses of placentas, want to be included in decision making, and desire information about the placenta. Placentas should not be viewed as "throwaway" organs that are poised for collection without the involvement and permission of women. Women want to be meaningfully included in research processes.

[Specificity versus representativeness: methodological approaches to the study of Mexico-U.S. migration]. / Especificidad versus representatividad: enfoques metodologicos en el estudio de la migracion mexicana hacia Estados Unidos.

PIP: "This article compares two sources of data on Mexico-U.S. migration, based on radically different methodologies: the Mexican Migration Project (Promig) and the National Survey of Population Dynamics (Enadid).... This comparative study shows that a micro-social design drawing on multiple community samples, such as Promig, can solve the methodological conflict between specificity and representativeness.... The authors' research also highlights the problem of selectivity and specificity entailed by traditional surveys such as Enadid as a result of restricting their samples to international residents in Mexico and attempting to explain such a complex, socioeconomic process using a limited number of variables." (EXCERPT)^ieng

Questionnaire approach to diagnosis in developing countries.

PIP: In developing country settings, health questionnaires have the potential to facilitate rapid diagnosis and early intervention. This methodology has been used, for example, to screen for schistosomiasis in China, Africa, and Brazil. Data can be gathered directly from individuals, through administrative channels (e.g., health centers and schools), or from secondary sources (e.g., censuses and surveys) obtained for other purposes. Costs are reduced and the refusal rate is lower than that associated with more invasive techniques. The questionnaire must be based on a sound knowledge of disease risk factors and symptoms. A diagnosis can be derived from a completed questionnaire through use of expert algorithms, medical reviews, or statistical methods. Collaboration between researchers and potential users of these simplified techniques is required to ensure the development of culturally appropriate tools and facilitate their adoption.^ieng

[Participatory observation in the 1995 count of population and housing. An anthropological experience]. / La observacion participante en el Conteo de Poblacion y Vivienda 1995. Una experiencia antropologica.

PIP: "The experience of an anthropologist who participated as enumerator in [Mexico's] Conteo de Poblacion y Vivienda 1995 is analyzed in this paper. The author describes briefly the methodology...for each stage of the enumeration; she systematically points [out] the circumstances and reasons that determine why the different groups involved in the process do not follow the rules. She [examines] the questions that the informers usually avoid answering, or the ones they answer hardly and imprecisely." (EXCERPT)^ieng

Comparing the Peru service availability module and situation analysis.

This report reviews the experience of the World Fertility Surveys and the Demographic and Health Surveys (DHS) in collecting community-level data on family planning. It assesses the validity of the community data for Peru that were collected via a service availability module, much like that which is used for the DHS, through a comparison with data from the Situation Analysis. The analysis indicates that the knowledgeable informant, the main source of information about family planning in each community for the service availability module, may not be an accurate source of data. Information about the availability of family planning services is more reliable when it is obtained by means of visits to service sites. However, given cost considerations, sampling problems, and analysis issues, routine linkage of Situation Analyses to household surveys such as the DHS is not recommended at this time.

PIP: Using data from the 1992 Demographic and Health Survey (DHS) in Peru, population researchers compared family planning data obtained by knowledgeable informants with family planning data from visits to health facilities to assess the validity of community data. The data were based on a total number of 239 clusters. 92.5% of the responses about the presence of hospitals were consistent. The situation analysis (SA) field team found three hospitals, while the knowledgeable informants said that 21 hospitals existed within a 5 km radius. 69% of responses about the presence of clinics and medical posts were consistent. The SA field team found 95 clinics or medical posts, while the knowledgeable informants said that there were 123. The consistency rate for pharmacies was 77%. The field team identified 23 pharmacies, while the informants claimed that there were 67. 60.6% of responses by the informants about the presence of any health provider were consistent with information obtained from an SA questionnaire. The consistency rate was highest for midwives (93.2%) and lowest for birth attendants (54.7%). These findings show that the knowledgeable informant in Peru is often not a reliable source of family planning data. Yet the service availability module assumes that the key informant is the main source of family planning information in each community. The findings also suggest that field visits to service delivery points generate more reliable family planning data. Nevertheless, the researchers did not recommend routine linkage of SAs to household surveys (e.g., DHS) due to relatively high costs, sampling problems, and analysis issues.

Congratulations to the mothers. Breastfeeding.

PIP: In Lima, Peru, a study was conducted that evaluated the influences on mothers' decisions regarding breastfeeding. Local views and health professional advice was ascertained. A follow-up study of a group of pregnant women was conducted to assess knowledge, attitude, and practice in regard to the early feeding of their children. The women were interviewed in their homes before delivery, as soon as possible after delivery, and twice a week until their babies were 1 month old. The experience of the mother was the key factor, but advice from relatives, neighbors, and health professionals was also important. A lack of information about exclusive breast feeding was common. Although the women knew breast feeding was good, they were unaware that exclusive breast feeding was best. Health workers knew to advise against other milks, but failed to advise mothers against the use of herbal teas and sweetened water as supplements. The women commonly believed they were unable to produce enough milk to feed their children because of their own undernourishment. Others believed exclusive breast feeding would worsen their own health, while some experienced difficulties breast feeding. This led to supplementation with other milks; herbal teas were given to cure colic and to quench infants' thirst. Based on these findings, the project focused educational efforts on providing better information to mothers. Messages stressed the thirst quenching property of breast milk and its similar benefits to herbal tea, which should be consumed by the mother, rather than the infant. Since breast feeding practices were closely linked to mothers' beliefs about their own needs, the project emphasized the value and needs of the mother and the benefits of breast feeding for her. Educational activities, which continued for 12 months, included videos shown to small groups of mothers, posters, distribution of pamphlets, and messages broadcast over loudspeakers. A significant increase in the number of children aged 0-4 months being exclusively breast fed was observed; however, the increase only occurred in the second, third, and fourth month. This seemed to be a direct result of the decrease in use of herbal teas and sweetened waters. The number of women using other milks as supplements did not decrease significantly.^ieng

Diagnostic accuracy of three clinical case definitions for advanced HIV disease.

OBJECTIVE: To assess the accuracy of three clinical case definitions for advanced HIV disease: the World Health Organization (WHO) case definition, and the original and revised Caracas case definitions. DESIGN: Retrospective chart review. SETTING: A clinic for patients with all stages of HIV infection at the Johns Hopkins Hospital, Baltimore, [correction of Bethesda] Maryland, USA, a tertiary care university hospital. PATIENTS, PARTICIPANTS: Two hundred and twenty-four HIV-positive adults who underwent initial evaluation between 1 January 1990 and 31 December 1990. MAIN OUTCOME MEASURES: A score for each definition was assigned based on initial evaluation. The sensitivity, specificity, and predictive values were calculated using the Centers for Disease Control (CDC) staging criteria, and results were correlated with total CD4 cell counts. RESULTS: The sensitivities of the WHO, and the original and revised Caracas definitions were 40, 67, and 60%, respectively, using CDC disease stage IV as a positive standard. Specificities were between 99 and 100%, using CDC stage II-III disease as a negative standard. Mean CD4 cell counts for patients with positive scores were 184, 160, and 158 x 10(6)/l, respectively, compared to 191 x 10(6)/l for CDC stage IV patients. Sensitivity was lower when the positive standard was expanded to include all patients with CD4 cell counts less than 200 x 10(6)/l. CONCLUSIONS: In our study population, case definitions were specific, but only moderately sensitive for advanced HIV disease. Prospective studies should be conducted in diverse geographic regions, using lymphocyte or CD4 cell counts when possible.

PIP: The 1st case definition for AIDS was developed by the Centers for Disease Control (CDC) in 1982. WHO adopted CDC definitions for use in some countries and also developed a clinical case definition where HIV serology tests were not feasible. A multivariate analysis of data of Brazilian AIDS patients with positive HIV serology provided the basis for the Caracas definition in 1989 and it subsequent revision. The accuracy of these 3 clinical definitions was evaluated to see their predictive value in an advanced stage of AIDS. The records of 224 HIV-positive adults were reviewed in 1990. Scores were assigned to various symptoms. 80% of men and 20% of women with a median age of 33 years; 1/4 were white and 2/3 were black. 1/3 were homosexuals and 1.2 were iv drug users. 139 were asymptomatic (CDC stage I-II) and 85 were symptomatic (CDC stage IV). 58 patients had total CD4 cell counts of over 500 x 1 million/1; 91 had 200-500 x 1 million/l; and 70 had 200 x 1 million/1. 48 were taking zidovudine and Pneumocytis carinii drugs. The sensitivities of the WHO, original Caracas definition, and revised Caracas definition were 40%, 67%. and 60%, respectively, with 99-100% specificities and positive predictive values of 97-100%. The mean CD4 cell counts for the WHO, original and revised Caracas definitions were 184, 160, and 158 x 1 million/1, respectively, compared with 199 x 1 million/1 of patients with CDC stage IV disease. The predictive values of the 3 definitions for CD4 cell counts 200 x 1 million/1 reached 62%, 73%, and 71% vs. only 59% for CDC stage IV patients. The combination of stage IV symptoms or a CD4 cell count 200 x 1 million/1 produced sensitivities of 31%, 53%, and 47%, respectively, with 100% specificity and positive predictive values. The definitions were highly specific, but only moderately sensitive for advanced AIDS; the Caracas definitions were more sensitive than the WHO definition.

The use of rectal tubes for stool collection.

PIP: Besides verifying the absence of wild poliovirus transmission in children with acute flaccid paralysis, the ICCPE also advocates verifying the absence of wild poliovirus transmission in the environment. This can be done either by community stool surveys of normal children or by sampling sewage. In developed countries, the sampling of sewage tends not be a constraint since adequate sewage systems exist. In developing countries where such systems do not always exist, or, if they do, they do not always operate, community stool surveys are preferable, especially in remote rural areas. In April 1991, staff from PAHO and the Ministry of Health of Colombia conducted a community survey of 242 5 year old children living in a high risk area of Cartagena, Colombia to compare the effectiveness of the traditional cup technique of collecting stool samples with the polyethylene rectal tube in screening normal children 5 years old. They chose this area of Cartagena because it has had several confirmed cases of polio. The rectal tube was to be inserted 66-75% of its length into the rectum. More children had their stools collected via the traditional cup technique than the rectal tube technique (67% vs. 36%; p.001). Isolation rates for enterovirus including poliovirus were similar for the 2 techniques. Thus the probability of getting stool samples from children 5 years old was 3 times greater with the traditional cup technique than the rectal tube technique. In fact, the collection rate for the rectal tube was so low, staff could not accurately evaluate the possibility of silent transmission among high risk children. PAHO advises then that health workers not use the rectal tube in the polio eradication program in the Americas until further research has been conducted.^ieng

Nutritional status of a nationwide sample of rural Mexican populations.

Information on nutritional status of the rural Mexican population is mostly obtained from cross-sectional studies. This investigation evaluates semi-longitudinally the nutritional level of a sample of the rural population of Mexico. A total of 15,552 individuals in 2,587 households from 208 rural communities were evaluated. Body weight and height of rural boys and girls were found to be significantly lower than in their urban counterparts. Severe forms of weight for age or height for age inadequacy were more frequent in females than in males, in smaller communities than in larger ones, and in economically depressed zones than in those with a good economy. Our data showed a lower frequency of mild and moderate forms of possible malnutrition than previous studies (20 vs 50%) using as a criterion weight for age. These differences are explained on the basis of sampling bias.

PIP: The nutritional status of 15,552 individuals of both sexes in 2587 households from 208 rural communities in Mexico was evaluated in a semilongitudinal nationwide study. Research was carried out from March 1982 to February 1983. The communities were randomly selected from among the 3000 with Mexican Institute of Social Security-COPLAMAR primary health care services. The 8 geoeconomic zones identified by Bassols-Batalla were represented. 10 families with at least 1 infant under 1 year old were selected in communities with under 5000 inhabitants, while 20 such families were selected from communities with 5001-20,000 inhabitants. Body weight, height or length, and arm and calf circumferences were measured in all household members in March-April 1982, and again in July-August 1982 and January-February 1983. The proportion of household heads employed primarily in agriculture ranged from 88% in the smaller communities to 32% in the larger. Families in small communities were mainly peasants in subsistence farming, while household heads in larger communities who were employed in agriculture were mostly owners of small plots. 40-54% of the mothers in communities of different sizes had 3 years or less of school attendance. Comparison of growth curves of the rural population with reference data from urban children showed similar median body weight in both groups at 2 years of age. But by age 18, median weight and height, respectively, were 8.6 kg lower and 9 cm shorter for rural boys and 5.5 kg lower and 5 cm shorter for rural girls. The most severe forms of inadequacy in weight for age were more frequent in females than males, in smaller communities than larger, and in the economically depressed zones. Severe inadequacy of height for age was more frequent in the states located on the southern Pacific Coast and the Gulf of Mexico. The frequency of mild and moderate forms of malnutrition according to weight for age was 20%, lower than the rate of 50% estimated in previous published studies. Selection of a broader range of rural communities rather than just the most marginal, and the bias introduced by selecting the sample from among communities with primary health services may explain the lower rate in this study.

[Colombia. Prevalence, Demography and Health Survey 1990]. / Colombia -- encuesta de prevalencia, demografia y salud 1990.

PIP: Colombia's 1990 Survey of Prevalence, Demography, and Health (EPDS) was intended to provide data on the total population and on the status of women's and children's health for use in planning and in formulating health and family planning policy. 7412 household interviews and 8647 individual interviews with women aged 15-49 years were completed. This document provides a brief description of the questionnaire, sample design, data processing, and survey results. More detailed works on each topic are expected to follow. After weighing, 74.8% of respondents were urban and 25.2% rural. 3.2% were illiterate, 36.6% had some primary education, 50.2% had secondary educations, and 9.9% had high higher educations. Among all respondents and respondents currently in union respectively, 98.2% and 997% knew some contraceptive method, 94.1% and 97.9% knew some source of family planning, 57.6% and 86.0% had ever used a method, and 39.9% and 66.1% were currently using a method. Among all respondents and respondents currently in union respectively, 52.2% and 78.9% had ever used a modern method and 33.0% and 54.6% were currently using a modern method. Among women in union, 14.1% currently used pills, 12.4% IUDs, 2.2% injectables, 1.7% vaginal methods, 2.9% condoms, 20.9% female sterilization, .5% vasectomy, 11.5% some tradition method, 6.1% periodic abstinence, 4.8% withdrawal, and .5% others. Equal proportions of rural and urban women were sterilized. The prevalence of female sterilization declined with education and increased with family size. Modern methods were used by 57.5% of urban and 47.7% of rural women, 44.0% of illiterate women, 51.8% of women with primary and 57.8% with secondary educations. Among women in union, 10.9% wanted a child soon, 19.7% wanted 1 eventually, 3.6% were undecided, 42.6% did not want 1, 21.4% were sterilized, and 1.2% were infertile. Among women giving birth in the past 5 years, the proportion having antitetanus vaccinations increased from 39% in 1986 to 55.5% in 1990; the proportion receiving prenatal care from a physician increased from 67 to 80%; and the proportion receiving medical assistance at delivery increased from 61 to 71%. Among children under 5, 66% of urban and 61% of rural residents were completely vaccinated. The proportion completely vaccinated ranged from 59% in the Atlantic province to 69% in the Eastern province. 48% of children of illiterate mothers and 68% of children whose mothers has higher educations were completely vaccinated. The proportion of children under 5 who suffered from diarrhea within the past 24 hours declined from 9.8 in 1986 to 4.6% in 1990 and the proportion with diarrhea in the preceding 2 weeks declined from 118.7 to 12.5%. 2/3 of the women knew about Pap tests and 46% had ever had 1. Almost all respondents knew about AIDS. 20% reported ever having been struck by their husbands.^ieng

Mexican-American adolescent sexuality and sexual knowledge: an exploratory study.

PIP: This article reports the findings of a study designed to examine the sexual knowledge, attitudes, and practices of low-income Mexican- American adolescents. The participants in the study were all about to begin a sex education program in a community health organization in East Los Angeles. The study involved 84 adolescents aged 14-19, 97% of who identified themselves as Mexican-American (the remainder identified themselves as Latino). 51 of the subjects were female and 33 male. The participants completed a 43-item questionnaire concerning demographics, sexual experience and contraceptive use, knowledge of birth control methods, and attitudes towards sexuality and birth control. Only 18 (21%) of the subjects indicated ever having sex. But among this group, 83% reported not using contraception during their last intercourse, and 61% reported never using contraception. Only 22% reported using contraception regularly. Concerning the knowledge of different birth control methods,many of the participants were able to list several methods, but their responses indicated a lack of accurate and specific knowledge about contraceptive methods. In addition to the 43-item questionnaire, 27 of the subjects also completed a sexual and contraceptive knowledge questionnaire. The topics included contraceptive effectiveness, the menstrual cycle, and fertilization. The scores on the questionnaire were low, with an average score of 33% of correct answers. Finally, all 84 participants responded to a sexual attitude questionnaire, which revealed a generally traditional attitude toward the importance of have children, virginity, and the relationship between sex and love.^ieng

[New approaches to the measurement of population internal spatial mobility]. / Nuevos enfoques para medir la movilidad espacial interna de la poblacion.

PIP: This work argues for a new and broader approach to measurement of internal spatial mobility that would place it in the context of interaction with other social processes. Spatial mobility is not an isolated event that can be considered an independent variable; it is instead a process that can only be fully understood through its interaction with the other demographic, economic, political, and social elements that form part of the life of a human being. This work attempts to demonstrate the necessity of considering changes in these processes simultaneously, and briefly describes different methods of measurement. The study of migration has traditionally focused on a restricted concept of change of residence of individuals and has ignored other forms of population movement, such as commuting or repeated short-term movements not entailing permanent change of residence. Explanatory models of migration have been essentially cross-sectional, but a longitudinal approach is needed to analyze spatial mobility simultaneously with other events in the family and professional life. Retrospective studies may provide data on events in the past. They have the advantage of requiring only 1 visit, but the disadvantage that interviews may be quite lengthy. Some attempts to verify the quality of data collected in comprehensive retrospective biographical surveys in Belgium have yielded promising results. Respondents appear to remember the order of events better than the exact dates. It is more difficult to conduct retrospective surveys in developing countries because of the usual lack of population registers and other documentation. Prospective surveys appear more appropriate for obtaining longitudinal data on spatial mobility, but difficulties of following the sample for long periods of time then arise. Visits must be repeated at short enough intervals to avoid errors of memory, and arrangements must be made in advance for locating respondents who migrate. A hypothetical example of analysis of data on marital status and migration using data from a prospective study illustrates the use of nonparametric statistical techniques for this type of analysis. Parametric methods generalize the procedures of multiple regression, allowing functional dependencies to be identified. A large number of explanatory variables can be analyzed in parametric models, making them very useful for understanding interactions between migration, family life, professional life, etc. Semi-parametric models are a synthesis of parametric and non-parametric and offer advantages of each. A broader focus on spatial mobility could be enhanced by a closer cooperation of demography with other social sciences.^ieng

Fertility change in Costa Rica 1960-84: analysis of retrospective lifetime reproductive histories.

Lifetime reproductive histories of a 1984-85 nationally representative sample of 870 women aged 25-59 years provided data to describe the evolution of fertility, contraception, breast-feeding, and natural fecundability in Costa Rica between 1960 and 1984. The contraceptive prevalence rate increased from 23% in 1965 to 58% in 1975 and 66% in 1984. Duration of breast-feeding was stable during the 1960s, decreased in the early 1970s, and increased after about 1976. Fecundability among women who did not practise contraception was lower than expected and declined between 1960 and 1975, probably because of selection effects. Despite a high consistency between estimations from the reproductive histories and other sources of data, some suggestion of omissions of short periods of contraceptive use in the distant past was detected. The survey may have reduced recall errors by using a calendar that summarizes major life events together. The analysis demonstrated the feasibility and usefulness of asking for lifetime reproductive histories in fertility surveys in developing countries.

PIP: Lifetime reproductive histories of a 1984 through 1985 nationally representative sample of 870 women aged 25 through 59 years provided data to describe the evolution of fertility, contraception, breast feeding, and natural fecundity in Costa Rica between 1969 and 1984. The contraceptive prevalence rate increased from 23% in 1965 to 58% in 1975 and 66% in 1984. Duration of breastfeeding was stable during the 1960s, decreased in the early 1970s, and increased after about 1976. Fecundability among women who did not practice contraception was lower than expected and declined between 1960 and 1975, probably because of the selection effects. Despite a high consistency between estimations from the reproductive histories and other sources of data, some suggestion of omissions of short periods of contraceptive use in the distant past was detected. The survey may have reduced recall errors by using a calendar that summarizes major life events together. The analysis demonstrated the feasibility and usefulness of asking for lifetime reproductive histories in fertility surveys in developing countries. Retrospective information gathered on 900 women permitted reconstruction of the results in a a period of dramatic changes. However, Costa Rica may be somewhat exceptional among developing countries because of its high levels of literacy. Some of the few, older, illiterate women may have found a life history calendar difficult to decipher, but others seemed to grasp the approach as easily as did the literate men.

[Identification of pregnant patients at risk of delivering low birthweight infants in urban areas of Guatemala]. / Identificacion de embarazos con riesgo de producir ninos de bajo peso al nacer en areas urbanas de Guatemala.

PIP: A prospective epidemiologic study of pregnant women obtaining prenatal care at a social security hospital in Guatemala City was the basis for an attempt to develop a method of identifying early in pregnancy women at risk of having low birth weight infants. Existing classifications of risk are not completely satisfactory for low income women in urban areas of developing countries. The sample included 17,135 women seen between April 1984 and January 1986. Women who had no prenatal care or who obtained it elsewhere were excluded. Social workers interviewed each woman at the 1st prenatal visit to obtain sociodemographic data. The nurses or physicians attending the women completed forms based on perinatal records developed by the Latin American Center for Perinatology and Human Development and adapted to local needs. A final visit was made just after delivery to complete the information in each file. Great care was taken to assure that the 24 examiners used the same standards for all measurement variables. The standardized data collection techniques were evaluated in a study of agreement between observers. The study was conducted in 4 sections covering sociodemographic variables, obstetric history, prenatal variables, and labor and delivery. Taking into account the size of the sample and the number of observers, it was concluded that the data were of acceptable quality. It is strongly recommended that periodic evaluation of the quality of data collected be included in all perinatal epidemiologic studies. It was also concluded that longitudinal studies of perinatal risk factors might not be needed in all regions or health areas; the association between the best known risk factors and the evolution of pregnancy has been established, and with few exceptions it appears to be relatively constant in all populations. It is recommended that perinatal services reduce the amount of data routinely collected to a minimum and apply the quality control and standardization procedures to a sample of patients and to all personnel completing records. This would assure an acceptable quality of data as a basis for medical or public health decision making. Relevant additional variables could be added as needed^ieng

Use of ethnographic research for instrument development in a case-control study of immunization use in Haiti.

A rapid ethnographic assessment of barriers to health service utilization was conducted to identify maternal factors predicting use of child immunizations in Haiti. Methods included four focus group interviews, four natural group interviews, individual interviews with 14 health care providers and participant observation at vaccination posts. Analysis of qualitative data identified five categories of maternal factors associated with immunization use: competing priorities, low motivation, socioeconomic constraints, perceived accessibility of services, fears about health or social consequences and knowledge and folk beliefs related to vaccines. Selected variables among these factors were incorporated into a survey instrument designed to compare mothers of completely vaccinated children (cases) with mothers of incompletely vaccinated children (controls). The questionnaire was administered to 299 randomly selected mothers (217 cases, 82 controls). Bivariate and multivariate analyses found that of the factors identified through ethnographic research, only vaccine-related knowledge was significantly associated with immunization status. The utility and constraints of using ethnographic research for instrument development in epidemiological studies are discussed.

PIP: A rapid ethnographic assessment consisting of 4 focus groups, 4 natural group interviews, 14 provider interviews and participant observation rally posts was combined into a questionnaire which was tested by chi square for use in predicting which Haitian mothers utilize immunization services. The study population were mothers of 1800 children 12-23 months old in the Mirebalais Area Community Health program in the central highlands of Haiti. The program uses the rally post system, with teams visiting villages at 6-week intervals. Audio tapes and written notes were reduced to lists of all possible barriers to maternal utilization, and then regrouped into 16 categories, under 5 topics: competing priorities, lack of motivation, socioeconomic constraints, perceived accessibility of posts, fears of health consequences and knowledge of folk beliefs about vaccines. 22 questionnaire items were then developed, which were edited by the overall project director without input from the ethnographer. The questions were administered to 299 mothers, 82 with incompletely immunized, and 217 with completely immunized children. The questions which significantly predicted complete vaccination by bivariate analysis were knowledge of the name of 1 or more vaccines or illnesses, the recommended number of doses, and the correct age to begin vaccinations. It was likely that time demands from subsistence farming and income generating activities also affected service utilization, but the women probably interpreted the question on employment incorrectly.

[A comparison of complete and truncated birth histories to measure fertility and child mortality]. / Comparacion entre las historias completas y truncadas de nacimientos para medir la fecundidad y la mortalidad de la ninez.

"During the latter part of 1986, national probability sample surveys of women of reproductive ages were carried out in... Peru and the Dominican Republic. These surveys were made as part of the Demographic Health Surveys project (DHS). In each country, one survey was conducted with the standard core questionnaire developed for DHS; the other survey was based on an experimental questionnaire. The major difference between the two questionnaires is the inclusion in the experimental one of a monthly calendar, which records pregnancies, contraceptive use, reasons for contraceptive discontinuation, breastfeeding, post-partum amenorrhea, post-partum abstinence, women's employment and place of residence for the period 1981-1986. This paper presents results from the first stage of the analysis of the Peruvian data: a comparison of basic characteristics of the two samples and an assessment of the completeness of reporting of recent births and infant and child deaths, i.e., a comparison of information in the truncated and full birth histories." (SUMMARY IN ENG)