Each family completed a primarily in-home assessment conducted by trained staff who were blind to family diagnostic status. Although protocol length varied by wave of assessment, parent assessments typically involved 9–10 hours of data collection and child assessments were typically 7 hours (except for annual interviews which took one hour) each spread over seven testing sessions. Families were compensated $300 for their involvement if the assessment was carried out on a one-child family and $375 if two children were involved. 70% of eligible court families and 93% of community canvassed families agreed to participate (overall participation rate was 84%).
