The validity and reliability of parents recall for routine Immunization in Cameroon: an evaluative study

IntroductionIn the absence of immunization documentations, parents recall is used to assess children immunization status. During the 2018 demograhpic and health survey in Cameroon, parents recall was the only source of information for 47% of chidren assessed for immunization coverage. The objective of this study was to determine the validity of parents recall for immunization using the vaccination card as the reference in Yaounde-Cameroon. MethodsThe study targeting parents of children aged 0-59months who had their childrens vaccination cards. The immunization history of each child was taken based on both parents recall and vaccination card. Using the vaccination card as a reference, the sensitivity, specificity, positive predictive value and negative predictive value of parents recall were calculated. The degree of agreement and the kappa statistics between the two methods were calculated using R version 4.1.0 (2021-05-18). ResultsA total of 529 households were visited and 87 elligible parents enrolled. Approximately 55.2% of the children were girls and 53% of them were aged 12-59 months. In total, 94.25% of the participants enrolled were one of the biological parents of the children, with mothers making the majority 86.20% of participants. When combined for all vaccines in the EPI (i.e. one dose BCG, 4 doses of OPV, 3 doses of pentavalent vaccine, 3 doses of PCV-13, 2 doses of rotavirus vaccine, one dose of measles/rubella vaccine and one dose of the yellow fever vaccine), the sensitivity, specificity, positive predictive value, and negative predictive value of parents recall were 63%, 60%, 90%, and 23% respectively. The degree of agreement between the two sources was highest for BCG(94%) and lowest with Polio2(32%). Parents recall(94%) was most likely to correctly predict BCG vaccination status of a child than using the scars on the forarm(74%). ConclusionOur conclusion is that validity and reliability of parents recall vary a lot across different vaccines and parents recall is not very reliable for immunization status assessment in children. Parents recall is preferred for verifying BCG immunization to scars on the forarm. In general, we recommend that parents recall for routine immunization should be used only as a last resort or for BCG, and measles and Yellow Fever vaccines.