Targeted exercise interventions on stress, anxiety, depression, and sleep disorders in PhD students

Table 4 Analysis of the Perceived Stress Scale, Generalized Anxiety Disorder 7-item scale, and Patient Health Questionnaire-9

Measurement	mean ± SD		Cohen’s d	Mean difference (95%CI)	P values
	Targeted exercise	Tai Chi			Group effect	Time effect	Interaction effect
PSS
Baseline	28.93 ± 1.85	28.34 ± 2.03	0.30	0.59 (-0.39 to 1.57)	0.001	0.001	0.013
8 weeks	13.13 ± 1.84	16.09 ± 1.86	-1.60	-2.96 (-3.91 to -2.06)
12 weeks	14.31 ± 2.02	19.03 ± 1.82	-2.46	-4.72 (-5.62 to -3.76)
GAD-7
Baseline	14.03 ± 1.33	14.00 ± 1.32	0.02	0.31 (-0.64 to 0.65)	0.001	0.001	0.001
8 weeks	5.88 ± 1.43	9.03 ± 1.59	-2.08	-3.16 (-3.93 to -2.46)
12 weeks	6.31 ± 1.49	11.16 ± 1.41	-3.34	-4.84 (-5.54 to -4.15)
PHQ-9
Baseline	14.06 ± 1.56	13.97 ± 1.60	0.06	0.93 (-0.69 to 0.86)	0.001	0.001	0.019
8 weeks	6.13 ± 1.56	8.19 ± 1.63	-1.29	-2.06 (-2.86 to -1.26)
12 weeks	6.88 ± 1.45	10.06 ± 1.54	-2.12	-3.19 (-3.91 to -2.46)

CI: Confidence interval; GAD-7: Generalized Anxiety Disorder 7-item scale; PHQ-9: Patient Health Questionnaire-9; PSS: Perceived Stress Scale.