Transdisciplinary translational science and the case of preterm birth.

Medical researchers have called for new forms of translational science that can solve complex medical problems. Mainstream science has made complementary calls for heterogeneous teams of collaborators who conduct transdisciplinary research so as to solve complex social problems. Is transdisciplinary translational science what the medical community needs? What challenges must the medical community overcome to successfully implement this new form of translational science? This article makes several contributions. First, it clarifies the concept of transdisciplinary research and distinguishes it from other forms of collaboration. Second, it presents an example of a complex medical problem and a concrete effort to solve it through transdisciplinary collaboration: for example, the problem of preterm birth and the March of Dimes effort to form a transdisciplinary research center that synthesizes knowledge on it. The presentation of this example grounds discussion on new medical research models and reveals potential means by which they can be judged and evaluated. Third, this article identifies the challenges to forming transdisciplines and the practices that overcome them. Departments, universities and disciplines tend to form intellectual silos and adopt reductionist approaches. Forming a more integrated (or 'constructionist'), problem-based science reflective of transdisciplinary research requires the adoption of novel practices to overcome these obstacles.

Longitudinal analysis of community health workers' adherence to treatment guidelines, Siaya, Kenya, 1997-2002.

OBJECTIVES: To investigate community health workers' (CHW) adherence over time to guidelines for treating ill children and to assess the effect of refresher training on adherence. METHODS: Analysis of 7151 ill-child consultations performed by 114 CHWs in their communities from March 1997-May 2002. Adherence was assessed with a score (percentage of recommended treatments that were prescribed), calculated for each consultation. Recommended treatments were those that were indicated based on CHW assessments. We used piecewise regression models to evaluate adherence before and after training. RESULTS: The average adherence score was 79.4%. Multivariable analyses indicate that immediately after the first refresher training, the mean adherence level improved for patients with a severe illness, but worsened for patients without severe illness. Adherence scores declined rapidly during the 6 months after the second refresher training. CONCLUSIONS: The first refresher was partially effective, the second refresher had an effect contrary to that intended, and patient characteristics had a strong influence on adherence patterns. Longitudinal studies are useful for monitoring the dynamics of CHW performance and evaluating effects of quality improvement interventions.

The influence of observation and setting on community health workers' practices.

OBJECTIVE: To determine whether results from an evaluation that involved observation of community health workers while they performed patient consultations in a hospital reflected normal everyday practices. DESIGN: Comparison of two samples of ill-child consultations: (i) consultations performed during an evaluation in which we observed community health workers in a hospital in-patient and outpatient department from February to March 2001 and (ii) consultations performed under no observation in villages and documented in clinical registers within the 90 days before the hospital evaluation. SETTING: Siaya District Hospital and villages in Kenya. STUDY PARTICIPANTS: Community health workers. MAIN OUTCOME MEASURE: Treatment error indicator, defined as the percentage of consultations where at least one recommended treatment (where recommended treatments were those that were indicated based on community health worker assessments of the child's condition) was not prescribed. RESULTS: We analyzed data on 1132 consultations (372 from the hospital evaluation and 760 from the community) performed by 103 community health workers. For all types of consultations combined, the difference between treatment error indicators (hospital minus community) was -16.4 [95% confidence interval (CI): -25.6, -7.1]. CONCLUSIONS: We found that community health workers made treatment errors less frequently when they were observed in a hospital in-patient or outpatient department than when they were not observed in the community. Evaluations that involve the observation of community health workers in a hospital setting might overestimate the quality of care that they normally give in their villages.

Cost-effectiveness of oral cholera vaccine in a stable refugee population at risk for epidemic cholera and in a population with endemic cholera.

Recent large epidemics of cholera with high incidence and associated mortality among refugees have raised the question of whether oral cholera vaccines should be considered as an additional preventive measure in high-risk populations. The potential impact of oral cholera vaccines on populations prone to seasonal endemic cholera has also been questioned. This article reviews the potential cost-effectiveness of B-subunit, killed whole-cell (BS-WC) oral cholera vaccine in a stable refugee population and in a population with endemic cholera. In the population at risk for endemic cholera, mass vaccination with BS-WC vaccine is the least cost-effective intervention compared with the provision of safe drinking-water and sanitation or with treatment of the disease. In a refugee population at risk for epidemic disease, the cost-effectiveness of vaccination is similar to that of providing safe drinking-water and sanitation alone, though less cost-effective than treatment alone or treatment combined with the provision of water and sanitation. The implications of these data for public health decision-makers and programme managers are discussed. There is a need for better information on the feasibility and costs of administering oral cholera vaccine in refugee populations and populations with endemic cholera.

PIP: The recent development of safe, reasonably effective oral cholera vaccines has made it possible to consider their use in situations where the risk of epidemic cholera is high. This article reviews the potential cost-effectiveness of the B-subunit killed whole-cell (BS-WC) oral cholera vaccine in both a stable refugee population and a population with endemic cholera. Baseline epidemiologic assumptions were applied to the standard populations to generate the expected morbidity and mortality levels for cholera and simple diarrhea; then, the net costs per case and per death averted by various interventions were calculated. In the population at risk for endemic cholera, the net costs per disability-adjusted life year (DALY) averted are considerably higher since incidence and access to health care are lower. In this population, mass vaccination with BS-WC vaccine is the least cost-effective intervention compared with the provision of safe drinking water and sanitation or with treatment of the disease. In the refugee population, the net costs per DALY averted are much lower since attack rates are higher and access to health care facilities is assumed to be 100%. In this population, the cost-effectiveness for vaccination is similar to that of providing safe drinking water and sanitation alone and less cost-effective than treatment alone or treatment combined with the provision of water and sanitation. Ultimately, the relative cost-effectiveness of an oral cholera vaccine will depend not only on its safety, effectiveness, and duration of protection against the El Tor biotype, but also on the feasibility of administering it to high-risk populations.

Economic impact of malaria in Malawian households.

Household heads were questioned about household income and household expenditures on the treatment or prevention of malaria in a nationwide malaria knowledge, attitudes, and practices (KAP) survey conducted in Malawi in 1992. Very low income households with an average annual income of $68 constituted 52% of the sampled households. The primary income source for these households was farm production (92%), with the majority of goods produced consumed by the household and not available as discretionary income. Expenditure on malaria prevention varied with household income level. Only 4% of very low income households spent resources on malaria preventive measures compared to 16% of other households. In contrast, over 40% of all households, independent of income level, reported expenditures on malaria treatment. Almost half of the reported malaria cases sought treatment at a health facility at a cost of $0.21 per child case and $0.63 per adult case. The overall direct expenditure on treatment of malaria illness in household members was $19.13 per year (28% of annual income) among very low income households and $19.84 per year (2% of annual income) among low to high income households. The indirect cost of malaria, calculated on the basis of days of work lost, was $2.13 per year (3.1% of annual income) among very low income households and $20.61 per year (2.2% of annual income) among low to high income households. Very low income households carried a disproportionate share of the economic burden of malaria, with total direct and indirect cost of malaria among these households consuming 32% of annual household income compared to 4.2% among households in the low to high income categories.

Malaria chemoprophylaxis compliance in pregnant women: a cost-effectiveness analysis of alternative interventions.

Compliance to malaria chemoprophylaxis among pregnant women in Malawi has historically been low. Three separate interventions, based upon an ethnographic study of malaria beliefs among pregnant women in Malawi, were introduced to increase compliance to the malaria chemoprophylaxis program provided by the Ministry of Health. Each intervention consisted of a health education message and an antimalarial drug. A cost-effectiveness analysis of the interventions was conducted to compare the interventions as alternative strategies to increase compliance among pregnant women.

Antenatal chloroquine chemoprophylaxis in Malawi: chloroquine resistance, compliance, protective efficacy and cost.

The roles of Plasmodium falciparum resistance to chloroquine and compliance in the protective efficacy of the antenatal chloroquine prophylaxis programme in Malawi were evaluated by interviewing pregnant women attending antenatal clinics and examining them for P. falciparum parasites in thick smears and chloroquine metabolites in urine. 36% of 642 women had urine chloroquine metabolite levels compatible with regular compliance to the weekly chloroquine dosage schedule. Among a subgroup of 288 pregnant women who were provided weekly prophylaxis under supervision for 4 consecutive weeks, P. falciparum infection rates were 37%, representing the failure of chloroquine to eliminate P. falciparum in Malawi. Among pregnant women not taking prophylaxis, the P. falciparum infection rate was 48%. Based on the P. falciparum infection rates among these 2 groups of women, the protective efficacy of CQ chloroquine was estimated as 23%. If the 36% of pregnant women who had chloroquine in their urines accurately estimates the proportion of women who comply with the prophylaxis programme in Malawi, the actual protective efficacy of the programme would be 8%. The cost of preventing one P. falciparum infection among pregnant women in the Malawi programme is estimated at US$ 10.87. This is an unacceptably high cost in much of Africa, and research is required to define more cost-effective interventions, including more effective drugs, and health education programmes to improve compliance among pregnant women.

PIP: During February-June 1988 in Malawi, interviews with and blood samples from 802 pregnant women attending 4 prenatal clinics on the shore of Lake Malawi or in the highlands were conducted to examine the role of chloroquine resistance and compliance in the protective efficacy of the government's chloroquine prophylaxis program. Compliance rates were 20% for women on their first prenatal visit and 36% for those on a return visit (i.e., urine chloroquine levels 1 ppm). 37% of 228 women who completed 4 weeks of supervised chloroquine administration had Plasmodium falciparum parasites in their blood. The P. falciparum infection rate was 48% among the 160 women who had not received supervised chloroquine administration. Based on these two rates, the protective efficacy of chloroquine was 23%. If the 36% of women on a return visit had taken their chloroquine as prescribed yet had chloroquine in their urine samples, the protective efficacy of the government's chloroquine prophylaxis program would have been 8%. Assuming an attack rate of P. falciparum of 48% and a protective efficacy of 8%, the cost per malaria case prevented would have been US $10.87. This is too high of a cost in Africa. Research is needed to identify more cost-effective interventions, such as more effective drugs and health education programs to improve compliance among pregnant women.

Oral rehydration therapy in Malawi: impact on the severity of disease and on hospital admissions, treatment practices, and recurrent costs.

In the first 2 years following refresher training of paediatric staff in oral rehydration therapy (ORT) and the establishment of an oral rehydration unit at the Kamuzu Central Hospital, Lilongwe, Malawi, there was a 50% decrease in the number of children admitted to the paediatric ward with the diagnosis of diarrhoeal diseases, a 56% decrease in the use of intravenous fluid to rehydrate such children, a threefold increase in the use of oral rehydration salts (ORS) exclusively to rehydrate children with mild or moderate dehydration, and a 39% decrease in the number of paediatric deaths associated with diarrhoeal diseases. Over the same period, there was a 32% decrease in recurrent hospital costs attributable to paediatric diarrhoeal diseases. As use of ORT continues to increase in Malawi, where diarrhoeal diseases account for 9% of paediatric hospital admissions, there should be considerable decreases in mortality from such diseases and concomitant increases in cost savings attributable to them.

PIP: In the 1st 2 years following refresher training of pediatric staff in oral rehydration therapy (ORT) and the establishment of an oral rehydration unit at the Kamuzu Central Hospital, Lilongwe, Malawi, there was a 50% decrease in the number of children admitted to the pediatric ward with the diagnosis of diarrheal diseases, a 56% decrease in the use of intravenous fluid to rehydrate such children, a 3-fold increase in the use of oral rehydration salts exclusively to rehydrate children with mild or moderate dehydration, and a 39% decrease in the number of pediatric deaths associated with diarrheal diseases. Over the same period, there was a 32% decrease in recurrent hospital costs attributable to pediatric diarrheal diseases. As use of ORT continues to increase in Malawi, where diarrheal diseases account for 9% of pediatric hospital admissions, there should be considerable decreases in mortality from such diseases and concomitant increases in cost savings attributable to them. (author's)

Oral rehydration therapy in Malawi: impact on the severity of disease and on hospital admissions; treatment practices; and recurrent costs

In the first 2 years following refresher training of paediatric staff in oral rehydration therapy (ORT) and the establishment of an oral rehydration unit at the Kamuzu Central Hospital; Lilongwe; Malawi; there was a 50 percent decrease in the number of children admitted to the paediatric ward with the diagnosis of diarrhoeal diseases; a 56 percent decrease in the use of intravenous fluid to rehydrate such children; a threefold increase in the use of oral rehydration salts (ORS) exclusively to rehydrate children with mild or moderate dehydration; and a 39 percent decrease in the number of paediatric deaths associated with diarrhoeal diseases. Over the same period; there was a 32 percent decrease in recurrent hospital costs attributable to paediatric diarrhoeal diseases. As use of ORT continues to increase in Malawi; where diarrhoeal diseases account for 9 percent of paediatric hospital admissions; there should be considerable decreases in mortality from such diseases and concomitant increases in cost savings attributable to them