Reliability and validity of the short form of the child health questionnaire for parents (CHQ-PF28) in large random school based and general population samples

STUDY OBJECTIVES: This study assessed the feasibility, reliability, and validity of the 28 item short child health questionnaire parent form (CHQ-PF28) containing the same 13 scales, but only a subset of the items in the widely used 50 item CHQ-PF50. DESIGN: Questionnaires were sent to a random regional sample of 2040 parents of schoolchildren (4-13 years); in a random subgroup test-retest reliability was assessed (n = 234). Additionally, the study assessed CHQ-PF28 score distributions and internal consistencies in a nationwide general population sample of (parents of) children aged 4-11 (n = 2474) from Statistics Netherlands. MAIN RESULTS: Response was 70%. In the school and general population samples seven scales showed ceiling effects. Both CHQ summary measures and one multi-item scale showed adequate internal consistency in both samples (Cronbach's alpha>0.70). One summary measure and one scale showed excellent test-retest reliability (intraclass correlation coefficient >0.70); seven scales showed moderate test-retest reliability (intraclass correlation coefficient 0.50-0.70). The CHQ could discriminate between a subgroup with no parent reported chronic conditions (n = 954) and subgroups with asthma (n = 134), frequent headaches (n = 42), and with problems with hearing (n = 38) (Cohen's effect sizes 0.12-0.92; p