Table 1. Characteristics of participants who remained in the study in comparison to those lost to follow-up.
| Attrition Group (n = 309) | Cohort in this report (n = 194) | p | |
|---|---|---|---|
| Gender | 0.93 | ||
| Male | 154 (50%) | 98(51%) | |
| Female | 155 (50%) | 96 (49%) | |
| Ethnicity | 0.002 | ||
| Caucasian | 166 (54%) | 131 (68%) | |
| Hispanic | 143 (46%) | 63 (32%) | |
| Family Income | 0.03 | ||
| <$40,000 | 68 (47%) | 68 (35%) | |
| ≥$40,000 | 76 (53%) | 126 (65%) | |
| Parent Education | 0.1 | ||
| <4 years college | 95 (61%) | 102 (53%) | |
| ≥4 years college | 61(39%) | 92 (47%) | |
| Age‡ | 9.0 (±1.6) | 8.7 (± 1.6) | 0.1 |
| Obstructive Sleep Apnea† | 58 (19%) | 31 (16%) | 0.5 |
| Insomnia§ | 80 (26%) | 52 (27%) | 0.8 |
| Insomnia (ICSD2-derived)** | 32 (11%) | 20 (10%) | 1 |
*All measurements were obtained in phase 1.
‡Age is reported as mean ± standard deviation.
†Obstructive sleep apnea was defined as an apnea-hypopnea index ≥ 1.5 on unattended polysomnography. OSA: obstructive sleep apnea.
§Insomnia requiring only the subjective complaint of problems falling asleep, staying asleep or waking too early in the morning.
**International Classification of Sleep Disorders (ICSD2) derived insomnia includes subjective complaint of problems falling asleep, staying asleep or waking too early in the morning with the additional requirements of ≥ 9 hours of time in bed as well as daytime symptom including learning problems, daytime sleepiness, or concern about not getting enough sleep.