Table 1.

Instruments used in Down syndrome NOW questionnaire that were included in analysis

Instrument	No. Items	Description of Instrument	Range of possible scores	Cohort mean (SD) & range of scores
SF12 Version 215 N = 250	12	Widely used and accepted generic measure of health status that covers the areas of physical functioning, pain, health, vitality, social functioning, and mental health. The higher the score the better the person’s health.	0–100	PCS: 50.2 (9.6); 18.2–67.1 MCS: 45.2 (10.6); 2.6–66.8
WeeFIM20 N = 223	18	Developed to measure the typical performance of children in essential self-care, mobility and communication-social learning skills. The higher the score the greater the child’s ability to complete essential daily tasks without parental assistance or supervision. It was previously adapted for questionnaire format in a study of children with Down syndrome.38	18–126	Mean: 94.2 (25.6) Range: 24–126
Developmental Behaviour Checklist18 N = 211	96	Assesses the behaviour and emotional disturbance in children and adolescents with mental retardation. 6 subscales. The higher the score the greater the child’s behaviour and emotional disturbance.	0–300	Mean: 36.6 (22.6) Range: 1–106 Prop. ≥ 44: 31.3%
Social Communication Questionnaire19 N = 213	40	A screening instrument for autism, previously known as the Autism Screening Questionnaire (ASQ) it helps evaluate communication skills and social functioning with all age groups with or without ID. Scores ≥ 15 recommended referral for a complete diagnostic evaluation	0–39	Mean: 11.1 (6.1) Range: 0–32