title: Educating adolescents about healthy sleep: experimental study of effectiveness of educational leaflet.
abstract: OBJECTIVE
  To evaluate how exposure to educational leaflet about healthy sleep affects knowledge about sleep in adolescents.
  
  
  METHODS
  The study included students aged 15-18 years from 12 high schools (1209 participants; 85% of eligible study population). Multistage sampling was used and the selected schools were randomly assigned into two intervention groups and two control groups, according to the Solomon experimental design. Intervention groups received educational leaflets and control groups did not. In one of the intervention groups and one of the control groups, pre-testing of knowledge about sleep was performed. Students answered the Sleep Knowledge Test, which was constructed in accordance with the information on the leaflet. Data were analyzed by four-way ANOVA and additional analyses of simple main effects were performed.
  
  
  RESULTS
  Positive effect of educational leaflet was found in students aged 15 (F = 28.46; P < 0.001), 16 (F = 5.74; P = 0.017), and 17 (F = 17.17; P < 0.001), but there was no effect in students aged 18 (P = 0.467). In male students, positive effect of the leaflet was found only in the group that had not been pre-tested (F = 6.29; P = 0.012), while in female students, it was found in both pre-tested (F = 26.24; P < 0.001) and not pre-tested group (F = 17.36; P < 0.001), with greater effect in pre-tested group (F = 5.70; P = 0.017). Female students generally showed better knowledge about sleep than male students (F = 95.95; P < 0.001).
  
  
  CONCLUSIONS
  Educational leaflets can be an effective first step in educating younger high school students about healthy sleep, with the method being more effective in female adolescents.
authors.affiliation: Institute for Medical Research and Occupational Health, Ksaverska c. 2. PO Box 291, HR-10001 Zagreb, Croatia.
authors.forename: Marija
authors.initials: M
authors.lastname: Bakotić
authors.forename: Biserka
authors.initials: B
authors.lastname: Radosević-Vidacek
authors.forename: Adrijana
authors.initials: A
authors.lastname: Kosćec
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D000704:Analysis of Variance; D001294:Attitude to Health; D003479:Curriculum; D005260:Female; D005500:Follow-Up Studies; D006266:Health Education / Q000379:methods*; D007722:Health Knowledge, Attitudes, Practice; D006304:Health Status; D006801:Humans; D008297:Male; D011336:Probability; D012016:Reference Values; D012307:Risk Factors; D012572:School Health Services / Q000458:organization & administration; D012680:Sensitivity and Specificity; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000517:prevention & control; D013664:Teaching Materials / Q000600:supply & distribution*; D013997:Time Factors