Adolescents' misinterpretation of health risk probability expressions.

OBJECTIVE: To determine if differences exist between adolescents and physicians in their numerical translation of 13 commonly used probability expressions (eg, possibly, might). DESIGN: Cross-sectional. SETTING: Adolescent medicine and pediatric orthopedic outpatient units. PARTICIPANTS: 150 adolescents and 51 pediatricians, pediatric orthopedic surgeons, and nurses. MEASUREMENT: Numerical ratings of the degree of certainty implied by 13 probability expressions (eg, possibly, probably). RESULTS: Adolescents were significantly more likely than physicians to display comprehension errors, reversing or equating the meaning of terms such as probably/possibly and likely/possibly. Numerical expressions of uncertainty (eg, 30% chance) elicited less variability in ratings than lexical expressions of uncertainty (eg, possibly). CONCLUSION: Physicians should avoid using probability expressions such as probably, possibly, and likely when communicating health risks to children and adolescents. Numerical expressions of uncertainty may be more effective for conveying the likelihood of an illness than lexical expressions of uncertainty (eg, probably).

Children at risk for accidental burns from hot tap water.

The American Academy of Pediatrics identifies young children at risk for accidental hot tap water (HTW) burns and recommends that HTW temperatures be set no higher than 49 degrees C (120 degrees F). Studies show that a temperature of 52 degrees C (125 degrees F) can cause a full-thickness skin burn in 2 minutes and a temperature of 54 degrees C (130 degrees F) can result in a full-thickness skin burn in 30 seconds. We sought to identify the risk for HTW injury and the knowledge about safety limits at our military installation. Sixty family housing units were selected at random for measurement of HTW temperature by both an electronic thermometer and a mechanical thermometer. Fifty-three (88.3%) and 44 (73.3%) units had temperatures greater than 52 degrees C (125 degrees F) and 54 degrees C (130 degrees F), respectively. We found temperatures that were unsafe at all heater settings. Most parents with children younger than 6 years (51%) were unaware of the danger of HTW to their children. We concluded that children living on our military post were at high risk for serious accidental HTW burns. Moreover, existing qualitative settings are not reliable indicators of safe temperatures. We recommend that health-care providers inform parents about the dangers of HTW burns to children and advise setting maximum HTW temperatures to the 49 degrees C (120 degrees F) recommended by the American Academy of Pediatrics.

Adolescent health needs and access to care in the Army medical system.

The United States Army Medical Department operates one of the largest comprehensive medical care systems. Health of adolescents is promoted by providing them with access to care without the impediment of direct monetary charge. This study defines the scope of health concerns and the availability of care for the common health problems of adolescents in this geographically widespread medical care system of high accessibility. In addition to common respiratory illness, more age-group-unique musculoskeletal, psychosocial, dermatologic, gynecologic, and sexuality-related problems are noted. Availability of care varies by location, with tertiary centers providing more services appropriate to developmental stage. These data are useful in planning improved health-care services appropriate to developmental stages of adolescents in the Army medical system as well as in other health-care systems.

Demographics of Military dependent children and adolescents: projected patient population shift.

The United States government provides health care for one of the largest beneficiary populations in the world. Approximately 796,500 (35%) of the 2.27 million dependent children of uniformed services personnel are adolescents (13 to 19 years old). Although the majority of dependent children are dependents of active duty personnel (74.7%), close to half of the adolescents (47.7%) are dependents of retired personnel. Recent geopolitical world changes and a perceived decreased threat to national security have led to a planned 25% reduction of the active duty force by 1996. The mean age of children beneficiaries will rise as a result. Pediatricians in the military and civilian contract physicians need to prepare for increased health care of older pediatric patients, particularly adolescents.

Anabolic Steroid and Ergogenic Drug Use by Adolescents.

Enhancement of body image and improvement of athletic performance, with anticipated gains in self-esteem, are the major motives underlying adolescent use of anabolic steroids and ergogenic drugs. The authors discuss prevalence and availability, side effects and monetary cost, dependency and withdrawal syndromes, and clinical management of adolescent abusers.

Effect of vitamin B6 supplementation on gentamicin nephrotoxicity in rabbits.

Therapeutic use of gentamicin (GM) in a clinical setting may result in nephrotoxicity, most commonly presenting as acute tubular necrosis (ATN). We have previously observed decreased plasma pyridoxal 5'-phosphate (PLP) levels in rabbits given therapeutic doses of GM and endeavor in this study to determine if vitamin B6 supplementation (B6S) could protect against the nephrotoxicity of GM. Twenty-one rabbits were randomly assigned to 1 of 7 treatment groups of 3 rabbits each. Three of the groups received 10 mg GM/kg with either 10 mg B6S, 100 mg B6S or 0.9% saline. Three of the groups received 40 mg GM/kg with either 10 mg B6S, 100 mg B6S, or normal saline. The control group only received 100 mg B6S. All treatments were administered im once daily for 5 d. Blood was drawn for chemical assays on day 0 prior to any treatments and 2 h after each respective treatment on days 1, 3 and 5. After 5 d, the rabbits were euthanatized and kidneys were excised for histological evaluation by light microscopy. At the 40 mg GM/kg/d dose, significant mild to moderate ATN was observed in the saline controls, which was prevented by either dose of B6S. Only a few animals given 10 mg GM/kg/d showed any renal pathology and that was minimal. Unexpectedly, 1 rabbit given only 100 mg B6S/d but no GM had interstitial nephritis with focal ATN. We conclude that vitamin B6 can protect against the nephrotoxicity of GM in rabbits, but that further study is needed on the possible nephrotoxicity of high doses of B6S.

Measles revaccination response in a school-age population.

Due to the dramatic upsurge in the incidence of measles, the American Academy of Pediatrics and the Immunization Practices Advisory Committee of the Centers for Disease Control revised their measles immunization policies in 1989 to include a routine two-dose schedule. The objectives of this study were the following: (1) determine the prevalence of immunologically measles-susceptible subjects in a previously vaccinated, school-age, military dependent population; and (2) assess risk factors to identify immunologically measles-susceptible subjects. Serum was collected just prior to measles revaccination and again 2 weeks later. Measles-specific IgG and IgM titers were determined by enzyme-linked immunosorbent assay. Immunologically measles-susceptible subjects constituted 9.8% of the population. The interval since previous measles vaccination was significantly related to pre- and postrevaccination IgG titers in a repeated-measures analysis of variance model. The magnitude of increase in IgG titer following revaccination and analysis of trend for proportions of measles-susceptible subjects were significantly related to the age of initial vaccination. This study supports continued measles revaccination; in addition, revaccination appears to be of greater value at 11 to 12 years of age than at 4 to 6 years of age.

Maximizing the informational content of vectorial data in the electrocardiogram.

Scalar electrocardiograms contain a great deal of vectorial data. The informational content of these data can be maximized by treating each angle as a point on a plane whose distance from the origin is equal to the magnitude of its vector. These points can be resolved into their horizontal and vertical coordinates. The coordinates are linear values and can therefore be subjected to standard statistical methodology.

Serological response to measles revaccination in a highly immunized military dependent adolescent population.

In the spring of 1986, there was a measles outbreak in the city of El Paso, Texas, with 92 cases reported to the City-County Health Department. Of those 92 cases, 31 (32%) occurred within a public high school's student population of 2524. A mass measles vaccination program was undertaken at that high school in order to limit the outbreak. The student enrollment included a military dependent population of 368 students. Despite documented histories of prior measles immunizations in this military dependent subgroup, three individuals contracted the disease. Since this subgroup of students represented a highly immunized adolescent population, it was of interest to serologically determine their immune status prior to and following reimmunization with the expectation that such a study would provide information relating to the level of "protective" immunity. Prevaccination and postvaccination sera were obtained from 95 students. Results of measuring anti-measles antibody activity by ELISA indicate that 13 (14%) students responded to revaccination and experienced a fourfold or greater rise in IgG antibody levels. There were no detectable IgM responses. All of the students who responded to revaccination produced an anamnestic response (IgG boost only). Since most of these individuals had received first immunizations at 15 months of age or older, these findings suggest that secondary vaccine failure (waning immunity) was responsible for the putative "lowered" immunity in these individuals, instead of primary vaccine failure (maternal antibody suppression). These findings support current recommendations for measles booster revaccination of school-age children and adolescents.

Sexually Transmitted Diseases Through the Ages.

The earliest recognized and traditionally described STDs, as well as HIV infection in the modern era, are discussed to show not only the evolution of their diagnosis and treatment, but also the complex nature of associated misconceptions, myths, and attitudes, some of which persist today.

Chlamydia trachomatis Infections in Adolescents.

C. trachomatis is the most common bacterial cause of sexually transmitted diseases in the U.S. and represents a major health threat to sexually active adolescents. This chapter addresses special features involving the occurrence, consequences, diagnosis, treatment, and prevention of chlamydial genital infections.

Sexual maturity rating: a marker for effects of pubertal maturation on the adolescent electrocardiogram.

The heart is known to participate in the adolescent growth spurt. A peak increase in transverse diameter coincides with peak height velocity during pubertal maturation. The effects of maturation on the adolescent ECG were explored using sexual maturity rating (SMR) as a marker. ECGs were obtained from 751 patients 8 to 20 years of age seen for routine physical examinations. A total of 33 standard ECG measures were analyzed, with subjects separated by sex and SMR. Different trends were seen in boys and girls during the course of maturation for the majority of R and S wave amplitude measurements. Lower mean amplitudes were seen consistently in more mature (SMR 4 and 5) girls than less mature girls and all boys. The clinical implication of these findings is illustrated by analysis of the sum of RV5 and SV2, one of the criteria for left ventricular hypertrophy, by sex and SMR. No significant difference in the sum is noted for boys across five SMR groups. Girls, in contrast, show a steady decrease in the sum with advancing maturation. These trends are not as clearly shown when subjects are grouped by broad chronologic age ranges, as had been the practice in developing current adolescent ECG tables. These findings suggest that development of standard ECG tables in which SMR and sex have been taken into account might enhance interpretation during adolescence.

"Latchkey". Three voices with one message.

Two to five million children, 6 through 13 years old, are unsupervised at home after school. This practice, called "latchkey," involves issues of children without adult supervision for periods of time and questions of safety and social isolation. There are no published age guidelines for "latchkey" or data on actual practice. To investigate age guideline opinions and the factors that influence them, a survey of pediatricians (the professional voice), military police (the legal voice), and parents (the popular voice) was undertaken. Solicited opinions concerned ages at which children can be left alone for brief or extended periods and can be allowed to babysit younger children. The three "voices" expressed similar mean ages and distributions for each of the "latchkey" questions. For less than 15 minutes without supervision, the means approximated 9 years; for periods of 1 hour or longer, 12 years; and for babysitting, 14 years. The data presented do not address actual or appropriate practice, but instead provide a basis to begin investigation.

Ineffectiveness of historical data in predicting measles susceptibility.

The Immunization Practices Advisory Committee ( ACIP ) has devised noninvasive, historical criteria for determining individuals who are susceptible to measles. These criteria, which involve proof of vaccination, are incorporated into school entrance regulations and are used to indicate people who require vaccination during outbreaks. In a recent measles epidemic in El Paso , TX, 120,000 records were screened using these criteria, and as a result 13,000 students were vaccinated. During this outbreak, 91 adolescents, who were susceptible to measles by ACIP criteria, were serologically tested for measles antibody. Although none of these students had documentation of vaccination, only 11.0% of them lacked measles hemagglutination-inhibiting (HAI) antibody at a titer of 5. Assuming a minimum cost for vaccine of +2.60 per dose, a conservative estimate of the cost to the El Paso Health Department for 20,000 doses of measles vaccine would be +52,000. If these data can be extrapolated to the total student population, then upwards of 85% of vaccinated students were already immune. Thus, +44,200 was spent unnecessarily. In addition, as the ACIP criteria did not select for measles susceptibility, an estimated 12,000 students in El Paso were not protected against measles. Other methods to determine measles susceptibility should be developed for optimal control of future outbreaks.