Rationale, aims and objectives: The current American Academy of Pediatrics policy calls for universal developmental screening (UDS) at the 18-month well-baby visit (18MWBV). In contrast, different clinical practice guidelines exist in other developed countries where only toddlers of concerned parents are referred for (selective) developmental screening (SDS). This study compares the expected benefit (EB) of these two strategies for monitoring children's behavioural development at the 18MWBV.

Method: A clinical decision analysis was performed, with EB defined as gain (probability of screening when appropriate + probability of not screening when appropriate) minus cost (probability of screening when not appropriate + probability of not screening when not appropriate). Accordingly, a strategy's EB referred to its efficiency at distinguishing between toddlers who need to be referred for screening and those who do not.

Results: The EB of the UDS strategy was estimated at -0.242. In contrast, the EB of the SDS strategy was much greater at 0.326. In fact, the EB of the UDS strategy could only equal or surpass that of the SDS strategy if screening toddlers with a problem was considered almost five times more important than not screening well toddlers. However, our monitoring effort should be more evenly distributed between these two imperatives. Also, the evidence in favour of the SDS strategy remained largely unchanged after considering a broad range of values for the (unique) probabilities in the decision tree.

Conclusion: There are many steps involved in the monitoring of children's early behavioural development, but when it comes to decide whether or not to use behavioural screening, there is evidence for adopting the SDS strategy, and screening only if a behavioural concern is being raised by parents.

Keywords: clinical decision making; decision trees; infant health; practice guidelines; preventive medicine; primary health care.

© 2020 John Wiley & Sons, Ltd.