Effect of diurnal temperature range on the outpatient visits for acute bronchitis in children: a time-series study in Hefei, China.

•Time-series analysis was conducted to quantify the impacts of DTR on childhood AB.•The risk of childhood AB increased significantly when DTR was above 10.9 °C.•In our study, female children and children aged 0–4 years appeared to be more sensitive to DTR effect than other children.•This study showed that the greatest effect of DTR on childhood AB was not acute, but occurred three days later.