an increasing trendp = 0.008
The segmented regression analysis (Figure 2 ) indicated no significant trend between PHQ‐9 score and BMI z ‐score when BMI < 2.68 (99.6th centile), but an increasing trend was observed when BMI z ‐score ≥ 2.68 (99.6th centile) (slope before breakpoint = 1.11 vs. after breakpoint = 12.89, p = 0.008).