Likelihood ratios of multiple cutoff points of the Taipei City Developmental Checklist for Preschoolers, 2nd version

Background/purpose: This study aimed to examine the reliability and clinical decision validities of the Taipei City Developmental Checklist for Preschoolers, 2nd version (the Taipei II, which was filled out by parents) and the screening procedures conducted in the medical setting.

Methods: Methodology research and case control study designs were adopted. A total of 310 dyads consisting of children who were developing typically and 196 dyads of children with developmental delays and age 5.5 to 35.5 months were recruited for validity test. Among them, 165 mothers filled out the questionnaire twice within 1 week to examine the test-retest reliability of the total score and individual items. Validity indexes of the single cutoff strategy and multiple cutoff strategies were analyzed. With two cutoff point strategies, the likelihood ratios (LR) of the three test results, positive, neutral, and negative, were calculated.

Results: The test-retest reliabilities of the total scores of the seven checklists of the Taipei II (rs = 0.54-0.89, p<0.05) and their individual items (agreement 92% to 100%) were acceptable, except for the 30-month checklist and three individual items. The positive LR (LR+) and negative LR (LR-) of the single cutoff strategy were acceptable with most LR+ more than 2, and all LR- less than 0.5. Most of the diagnostic odds ratios of single cutoff strategies were less than 50 and they did not meet the acceptable criteria. When multiple cutoff points were used, all of the LRs with positive test results were equal to infinity that met SpPin criteria, and all of the LRs with negative test results less than 0.5 had at least a small but important diagnostic impact.

Conclusion: Taipei II with multiple cutoff points could give more useful clinical information than using a single cutoff point. The multiple likelihood ratios of Taipei II for children older than 3 years and in different cultural backgrounds need further study.