A comparison of educational interventions. Multimedia textbook, standard lecture, and printed textbook.

OBJECTIVE: To compare the instructional effectiveness and efficiency of a pediatric multimedia textbook (MMTB) with that of a standard lecture and of a printed textbook in a prospective, interinstitutional study. DESIGN: Randomized, prospective cohort. SETTINGS: An urban and a rural medical school affiliated with tertiary care hospitals. POPULATION: Third- and fourth-year medical students from June 1992 to June 1993. INTERVENTIONS/OUTCOME MEASURES: Students were randomized to one of four treatment groups: (1) computer-aided instruction with MMTBs (n = 39), (2) traditional lecture (n = 39), (3) printed textbook (n = 39), or (4) a control group (n = 62). Only the control group was pretested. Following their randomized instruction, all groups were tested via a 26-question multiple-choice test. Statistical analysis was accomplished by analysis of variance of mean post-test scores. The amount of time that students spent with each educational intervention was recorded. RESULTS: Three hundred two students were eligible for the study, 267 entered the study, and 179 completed the study. The instructional effectiveness of the MMTB was greater than that of the lecture (P < .05), and it was the same as that of the printed textbook. All instructional methods were more effective than the control group (P < .05). The instructional efficiency of the MMTB was equal to that of the lecture and of the printed textbook. The subjective response to the MMTB instruction was positive. CONCLUSION: The MMTBs constitute an educationally sound alternative instructional method and have a promising future in medical education.

The long-term outcome of nonsuppurative otitis media with effusion.

Seventy-four children were enrolled in a double-blind placebo-controlled study to define the outcome of nonsuppurative otitis media with effusion (OME) over a 12-week period. Participants were randomly assigned to one of three treatment groups: pseudoephedrine (4 mg/kg/day), chlorpheniramine (0.35 mg/kg/day), or placebo. The children were reexamined at 2, 4, 8, and 12 weeks after enrollment unless earlier dismissed from the study because OME resolved or acute suppurative otitis media developed. Of the 66 children completing the study protocol, 44 percent had resolved OME, 38 percent developed acute suppurative otitis media, 14 percent had unresolved OME, and 4 percent developed severe hearing loss or medication side effects by the end of 12 weeks. The greatest incidence of both suppurative otitis media and resolution of OME occurred by 2 weeks of follow-up. There was no significant difference in resolution of effusion between treatment groups. Children who were 18 months of age or older with unilateral effusion had the best likelihood of resolution.

Gastrointestinal side effects with erythromycin preparations.

This study was designed to determine the incidence and severity of gastrointestinal (GI) side effects in patients taking erythromycin. More patients complained of GI side effects with the enteric-coated tablet (70.8 percent) than with the stearate (51.4 percent) or the ethylsuccinate (48.9 percent) salts. The enteric-coated tablet was associated with a higher incidence of individual adverse reactions; more patients discontinued it because of adverse GI effects. These data demonstrate a high incidence of GI side effects to erythromycin. Additionally, GI side-effect incidence appears to be higher with the enteric-coated tablet.

Gender-related differences in iron absorption by preadolescent children.

In a study of absorption of iron from meals by preadolescent children (Tanner stage 1), we had noted that erythrocyte incorporation of the extrinsic iron label was somewhat greater by girls than by boys. Although the difference was not significant, the observation seemed to warrant further study. Study A: A precisely determined quantity of ferrous sulfate enriched with the stable isotope 58Fe was given without food to 15 boys and 15 girls (Tanner stage 1) after an overnight fast and was immediately followed by a dose of 70 mg of ascorbic acid. 58Fe enrichment of the erythrocytes was determined by inductively coupled plasma mass spectrometry at baseline and 14 and 42 d after administration of the 58Fe dose. Geometric mean erythrocyte incorporation of the 58Fe label was 35.2% of intake by boys and 45.0% of intake by girls. The difference was significant (analysis of covariance with serum ferritin as covariate, p = 0.035). Study B: Fifteen boys and 15 girls (Tanner stage 1) were fed a breakfast labeled with 58Fe. Geometric mean erythrocyte incorporation of the 58Fe label was 14.8% of intake by boys and 24.7% of intake by girls. The difference was significant (analysis of covariance with serum ferritin as covariate, p = 0.004). Because serum ferritin concentrations were similar in boys and girls, the gender-related difference in iron absorption (as reflected by erythrocyte incorporation of the label) does not appear to be explained by a difference in body stores of iron. We hypothesize that hormonal differences between boys and girls in Tanner stage 1 favor iron absorption by girls.

Use of the stable isotope, 58Fe, for determining availability of nonheme iron in meals.

Because of reluctance to use radioisotopes for studies of iron absorption in children, we have explored the feasibility of using the least abundant stable isotope of iron, 58Fe (natural abundance, 0.322 weight %) in a study of nonheme iron absorption. With a balanced cross-over design, each of 16 school-age children was fed a standardized lunch on 3 consecutive days and, 28 days later, an alternate standardized lunch on 3 consecutive days. The lunch included either a beef patty or a beef-soy patty. The mass isotope ratio, 58Fe/57Fe (MIR58/57), was measured in blood by inductively coupled plasma mass spectroscopy before and 14 days after (i.e. study day 15) consuming the three lunches. The MIR58/57 on study day 15 was used as a baseline value for lunches fed on study days 29, 30, and 31. Incorporation of 58Fe into erythrocytes was greater from the lunch with beef patty than from the lunch with beef-soy patty (geometric mean values 2.02 and 1.05% of the dose, p less than 0.03). Based on the similarity of our results with those obtained in adults with radioisotopes, we conclude that 58Fe is a satisfactory tag for studies of nonheme iron absorption from meals.