In the final analysis, only three children had an etiology that was identified by specialty evaluation and laboratory testing. Laboratory studies in these children were largely directed by clinical suspicion and served to support a probable diagnosis already apparent from the history and physical examination findings. The authors conclude that children with developmental language disorder must undergo audiometric assessment but that additional testing without indication is unlikely to be helpful. For those with motor delay, a high diagnostic yield can be expected, especially if there are physical findings in addition to motor delay. Language delay is the most common developmental problem you will see.
Significant delays are easy to spot, subtle ones are less so.
To be sure a child is language-delayed in questionable cases you need to use a valid language assessment instrument. The authors conclude that a diagnosis of DLD warrants careful audiometric evaluation but little else in the way of diagnostic work-up. They compare this finding to the work-up of motor delays, which had a much higher diagnostic yield. I like this study because it negates a shotgun approach to the work-up of all developmental problems and forces us to be more selective in our utilization of diagnostic studies. And now Mexican investigators suggest that the prolongation of the QT interval occasionally seen in children is not clinically significant.