The study examined developmental screening and communication delays in infants from underserved PHC contexts in South Africa. More specifically the Road to Health Booklet (RTHB) checklist was compared to a standardized international tool i.e. the PEDS tools, consisting of the PEDS and PEDS: DM. The relationship between psychosocial risks and communication delays was determined. The study also reported on the prevalence and nature of communication delays in these infants. Finally the study evaluated the accuracy of the PEDS tools to detect communication delays, against an internationally accepted diagnostic assessment tool, the Rossetti Infant Toddler Language Scale (RITLS).
A comparative cross-sectional within-subject design was employed. Parent interviews to obtain background information, the PEDS tools, the RTHB developmental checklist and Rossetti Infant Toddler Language Scales (RITLS) were used to collect data from caregivers of 201 infants, aged six to 12 months, selected through convenience sampling, at PHC facilities in the Tshwane district, South Africa.
Sensitivity of the RTHB developmental checklist was determined to be low (25%), but specificity values were high (86%-91%). The RTHB developmental checklist failed to identify more than half the infants at risk of delays or disorders. Hence, based on the results of this study, the nationally implemented developmental checklist was found to be ineffective in identifying at-risk infants. It is strongly recommended that the tool be adapted and validated or replaced in order to improve identification of at-risk infants.
Associations between communication delays and risks were determined using Chi-square and Fisher s exact non-parametric test statistics and a log linear model was built to model the simultaneous effect of significant risks on the probability of having communication delays.
Communication delays were present in 13% of infants. Association between three risk factors (i.e. housing status, age of mother and number of siblings) and language delays was established. Infants with two or more siblings, born from mothers aged 18-29 years who own their house have for example a 39% chance of presenting with communication delays. The impact of combined risk factors on language development revealed that an infant was at greatest risk (27% probability) of developing a language delay when 1) mothers were between the ages of 19 to 34 years; 2) when parents owned their own home and; 3) when there were three or more children in the household.
The prevalence of communication delays in the sample population was high possibly due to the majority of infants being exposed to risks. The implementation of preventative measures, such as awareness campaigns and developmental screening and surveillance should be considered in the South African PHC context. This is especially relevant since a clear relationship has been established between three risks and communication delays in infants.
The PEDS tools had low to very low expressive- and receptive language sensitivity scores across all three screens (ranging between 14%-44%). However, high sensitivity (71%) and specificity (73%) ratings for the receptive and expressive language and social emotional domain in combination were calculated. The results of this study may indicate that the PEDS tools may be an appropriate developmental screening tool for the detection of communications delays in infants in the South African PHC context. Future research determining accuracy of the PEDS, PEDS: DM and PEDS tools for children aged two to five years in detecting communication delays should be prioritised.