Please note: In 2003, the CTF updated its Grades of Recommendations to include an "I Recommendation" for situations where insufficient evidence exists to allow a recommendation to be made.  (Formerly, these situations were captured under a "C Recommendation".)  This change is not retroactive, and all "C Recommendations" made prior to 2003 have not been reevaluated in light of the new "I" recommendation grade.  For a discussion of these recommendation grades, please link to the 2003 article in the Canadian Medical Association Journal here.

Prepared by John W. Feightner, MD, MSc, FCFP, Department of Family Medicine, The University of Western Ontario

Objective
To make recommendations for screening of Canadian preschool children (age 3 to 5 y) for developmental problems. This is an update of the Canadian Task Force 1989 guideline.

Burden of Suffering
Good data describing the prevalence of school performance problems are difficult to find. The reported prevalence has varied from 6% to 30%; an arguable estimate is 16% to 20%. The rates have depended on factors such as the socioeconomic status of the population studied (children in lower socioeconomic groups tend to have more difficulties), the definition of school problems and the stage in the educational process at which an outcome is measured.

Options
Screening tests include the Denver Developmental Screening Test (DDST), Developmental Indicators for the Assessment of Learning (DIAL), Early Screening Inventory (ESI), Minneapolis Preschool Screening (MPS) instrument, the McCarthy Screening Test, McCarthy Screening Test, and the Jansky Screening Index (JSI).

Outcomes
Sensitivity and specificity of the screening tests, comparison of children who received or did not receive screening, and adverse effects of incorrectly labelling children with positive test results (delayed development). Interventions and assessment tools were special education services, academic achievement, cognitive and perceptual motor tests, and behavioural, social and emotional well-being.

Evidence
MEDLINE was searched to 1993 using the MeSH terms child development disorders, mass screening, reading or perceptual disorders, evaluation studies, longitudinal studies, and randomized controlled trials.

Values
The 13-member Task Force of experts in family medicine, geriatric medicine, pediatrics, psychiatry and epidemiology used an evidence-based method for evaluating the effectiveness of preventive health care interventions. Recommendations were not based on cost-effectiveness of options. Patient preferences were not discussed.

Background papers providing critical appraisal of the evidence and tentative recommendations prepared by the chapter author were pre-circulated to the members. Evidence for this topic was presented and deliberated upon in 1- to 2-day meetings, 2 to 3 times per year from January 1993 to June 1993. Consensus was reached on final recommendations.

Benefits, Harms, and Costs

Test Sensitivity/Specificity Comments

DDST
The reported sensitivity and specificity of the DDST have varied considerably; in one study they were 29% and 89% respectively, whereas in another they were 5% to 10% and 99%.  Further, due to its low sensitivity, the DDST fails to identify 90% to 95% of children with developmental problems.

DIAL
This instrument appears to have considerable potential (sensitivity 46% to 54% and specificity 93%), but more research is required to establish its reliability and validity.

ESI
Relatively easy to administer (takes 15 to 20 minutes to perform) and has a high sensitivity (81% to 100%), but a lower specificity (67% to 72%).  The reliability of the results depends on the training of the examiner.

MPS
Educationally oriented, brief and economical to administer and has achieved a sensitivity of 60% to 63% and a specificity of 89% to 93%.<11> It shows promising reliability and validity.

JSI
Specificity and sensitivity of 50% and 90% to 92%, respectively.

The DDST was assessed in 4671 children in Ontario in a randomized controlled trial. 18% of children did not received DDST testing (control group). Children who had positive DDST scores were randomly allocated to received intervention (assessment by a physician, parent counselling, a review done in conjunction with the teacher and school nurse, and monitoring by the school nurse). Overall, the children with positive test results did not differ from children who had negative scores for most outcome measures. The outcomes for the 2 groups with positive scores (intervention or no intervention) did not differ except that more parents with children in the intervention group were measured to be more worried about their children, compared with to parents who had children who were not in the intervention group (extensive follow-up).

One RCT of older children (mean age 10 y) with poor academic performance were allocated to a motivated remedial reading group or a control group. The intervention group received 54 sessions over 18 weeks and the students showed higher scores in all reading tests. The effect was transient and the teachers did not rate the children in the intervention group as being improved in general academic performance. Evidence suggests that early grade teachers may be better predictors of future school problems than available detection tools.

Recommendations
Recommendation grade [A, B, C, D, E]  and level of evidence [I, II-1, II-2, II-3, III] are indicated after each recommendation. Citations in support of individual recommendations are identified in the guideline text.

• Fair evidence exists to exclude, from the periodic health examination of children ages 3-5 years, the Denver Development Scale from the periodic health examination to determine developmental delays in preschool children [D, I].
• There is insufficient evidence to include or exclude, in the periodic health examination of children aged 3-5 years, the use of Oother detection tools for to detect developmental delays [C, II] in preschool children have insufficient evidence to either include or exclude from the periodic health examination [C, II].

Sponsors
The Canadian Task Force on Preventive Health Care developed this guideline with funding from Health Canada.

Selected References

Source Document
Feightner, J.W. Preschool screening for developmental problems. In: Canadian Task Force on the Periodic Health Examination. Canadian Guide to Clinical Preventive Health Care. Ottawa: Health Canada, 1994; 290-296.

Other
Canadian Task Force on the Periodic Health Examination: The periodic health examination: 1989 update part 3, Preschool examination for developmental, visual and hearing problems. Can Med Assoc J. 1989;141:1136-40.