The Malawi Developmental Assessment Tool (MDAT): the creation, validation, and reliability of a tool to assess child development in rural African settings

Abstract

Background: Although 80% of children with disabilities live in developing countries, there are few culturally appropriate developmental assessment tools available for these settings. Often tools from the West provide misleading findings in different cultural settings, where some items are unfamiliar and reference values are different from those of Western populations.

Methods and findings: Following preliminary and qualitative studies, we produced a draft developmental assessment tool with 162 items in four domains of development. After face and content validity testing and piloting, we expanded the draft tool to 185 items. We then assessed 1,426 normal rural children aged 0-6 y from rural Malawi and derived age-standardized norms for all items. We examined performance of items using logistic regression and reliability using kappa statistics. We then considered all items at a consensus meeting and removed those performing badly and those that were unnecessary or difficult to administer, leaving 136 items in the final Malawi Developmental Assessment Tool (MDAT). We validated the tool by comparing age-matched normal children with those with malnutrition (120) and neurodisabilities (80). Reliability was good for items remaining with 94%-100% of items scoring kappas >0.4 for interobserver immediate, delayed, and intra-observer testing. We demonstrated significant differences in overall mean scores (and individual domain scores) for children with neurodisabilities (35 versus 99 [p<0.001]) when compared to normal children. Using a pass/fail technique similar to the Denver II, 3% of children with neurodisabilities passed in comparison to 82% of normal children, demonstrating good sensitivity (97%) and specificity (82%). Overall mean scores of children with malnutrition (weight for height <80%) were also significantly different from scores of normal controls (62.5 versus 77.4 [p<0.001]); scores in the separate domains, excluding social development, also differed between malnourished children and controls. In terms of pass/fail, 28% of malnourished children versus 94% of controls passed the test overall.

Conclusions: A culturally relevant developmental assessment tool, the MDAT, has been created for use in African settings and shows good reliability, validity, and sensitivity for identification of children with neurodisabilities.

Figure 1. Stages in creation of final MDAT tool.

Draft MDAT I created out of 110 items from the preliminary study with the addition of 52 items from the qualitative study, as well as the modification of some items. Draft MDAT II created after face and content validity with addition of 13 items and eight items removed as well as the modification of some items. Draft MDAT III created after piloting where nine gross motor, six fine motor, nine language, and four social items were added or modified, and one gross motor, five language, and three social items were removed. The Final MDAT tool consisted of 136 items with 34 in each domain having had eight gross motor, nine fine motor, 23 language, and nine social items removed.

Figure 2. Example of the Draft MDAT III (gross motor domain).

Figure 3. Flow diagram of the recruitment of families and children for the MDAT study.

Figure 4. Normal reference values for gross motor milestones.

Figure 5. Normal reference values for fine motor milestones.

Figure 6. Normal reference values for language milestones.

Figure 7. Normal reference values for social milestones.