Effectiveness of a cognitive behavioural intervention on mental health in young footballers: A quasi-experimental study

Table 1 Contents and tasks of the intervention programme

Session	Content	Between-session tasks
Session 1	Programme information, psychological assessment	None required
Session 2	Goal setting	Weekly recording of performance goals for training sessions and matches
Session 3	Motivation workshop	Motivation diary
Session 4	Activity: Goal-setting work	None required
Session 5	Attention workshop	Practise the mini routine selected during the workshop in training sessions and subsequently apply it in matches. Record perceived effectiveness
Session 6	Activity: Attention work	None required
Session 7	Visualisation workshop	Carry out one visualisation rehearsal before training/competition, following the script developed
Session 8	Activity: Group cohesion work	None required
Session 9	Activation workshop	Design a personal plan: Two strategies to increase activation and two to decrease it before/during matches; brief in-room rehearsal
Session 10	Confidence workshop	Functional analysis: ABC
Session 11	Programme closure, psychological assessment	None required

Table 2 Pre-post changes by group in trait anxiety (Wilcoxon and Rosenthal’s r), mean ± SD

Group	Pre-test	Post-test	Z (Wilcoxon)	P value	r (Rosenthal)
Control	22.38 ± 5.71	22.97 ± 6.74	-1.000	0.317	0.18
Experimental	21.71 ± 5.43	20.92 ± 4.87	-1.099	0.272	-0.22

Z: Test statistics of the Wilcoxon signed-rank test (normal approximation); P: Probability value associated with the within-group comparison; Rosenthal’s r: Effect size calculated from Z and n (|10| = small, |30| = medium, |50| = large).

Table 3 Comparison between groups in trait anxiety (Mann-Whitney and Hedges’ g)

Moment	Group	Sample size	mean ± SD	P value	g (Hedges)
Pre-test	Control	32	22.38 ± 5.71	0.914	0.118
	Experimental	24	21.71 ± 5.43
Post-test	Control	32	22.97 ± 6.74	0.327	0.336
	Experimental	24	20.92 ± 4.87

P: Probability associated with the contrast statistic (Mann-Whitney U test in intergroup comparisons); Hedges’ g: Effect size corrected for independent samples (0.20 = small, 0.50 = medium, 0.80 = large).

Table 4 Pre-post changes by group in the Depression Anxiety Stress Scales-21 (Wilcoxon test and Rosenthal’s r), mean ± SD

Subscale	Group	Pre-test	Post-test	Z (Wilcoxon)	P value	r (Rosenthal)
Depression	Control	4.13 ± 3.66	5.78 ± 4.88	-1.701	0.089	-0.30
	Experimental	3.00 ± 2.98	3.46 ± 2.99	0.639	0.523	0.13
Anxiety	Control	5.75 ± 5.05	5.25 ± 4.28	-0.388	0.698	-0.07
	Experimental	2.92 ± 3.24	3.25 ± 3.04	-0.196	0.844	-0.04
Stress	Control	6.50 ± 5.08	6.38 ± 4.93	-0.226	0.821	-0.04
	Experimental	4.58 ± 3.12	3.79 ± 3.89	-1.388	0.165	-0.28

Z: Test statistics of the Wilcoxon signed-rank test (normal approximation); P: Probability value associated with the within-group comparison; Rosenthal’s r: Effect size calculated from Z and n (|10| = small, |30| = medium, |50| = large).

Table 5 Comparison between groups in Depression Anxiety Stress Scales-21 (Mann-Whitney and Hedges’ g)

Subscales	Moment	Group	Sample size	mean ± SD	P value	g (Hedges)
Depression	Pre-test	Control	32	4.13 ± 3.66	0.249	0.328
		Experimental	24	3.00 ± 2.98
	Post-test	Control	32	5.78 ± 4.88	0.103	0.548
		Experimental	24	3.46 ± 2.99
Anxiety	Pre-test	Control	32	5.75 ± 5.05	0.010b	0.639
		Experimental	24	2.92 ± 3.24
	Post-test	Control	32	5.25 ± 4.28	0.068	0.519
		Experimental	24	3.25 ± 3.04
Stress	Pre-test	Control	32	6.50 ± 5.08	0.244	0.434
		Experimental	24	4.58 ± 3.12
	Post-test	Control	32	6.38 ± 4.93	0.039a	0.564
		Experimental	24	3.79 ± 3.89

^aP < 0.05.

^bP < 0.01.

P: Probability associated with the contrast statistic (Mann-Whitney U test in intergroup comparisons); Hedges’ g: Effect size corrected for independent samples (0.20 = small, 0.50 = medium, 0.80 = large).

Table 6 Pre-post changes by group in Profile of Mood States (Wilcoxon and Rosenthal’s r), mean ± SD

Subscales	Group	Pre-test	Post-test	Z (Wilcoxon)	P value	r (Rosenthal)
Tension	Control	8.22 ± 4.52	12.47 ± 2.55	-3.820	< 0.001c	-0.68
	Experimental	6.83 ± 4.36	10.92 ± 2.32	-3.260	0.001c	-0.67
Depression	Control	4.00 ± 3.48	9.03 ± 3.48	4.504	< 0.001c	0.80
	Experimental	2.88 ± 3.18	7.75 ± 2.69	-3.564	< 0.001c	-0.73
Anger	Control	11.22 ± 6.33	9.88 ± 4.82	0.891	0.373	0.16
	Experimental	9.46 ± 4.95	7.88 ± 3.64	-1.631	0.103	-0.33
Vigour	Control	12.88 ± 3.20	6.19 ± 2.48	-4.595	< 0.001c	-0.81
	Experimental	12.54 ± 2.52	6.13 ± 3.38	-4.021	< 0.001c	-0.82
Fatigue	Control	6.28 ± 4.03	4.88 ± 4.02	-1.832	0.067	-0.32
	Experimental	5.33 ± 4.44	3.00 ± 3.24	-2.553	0.011a	-0.52

^aP < 0.05.

^cP < 0.001.

Z: Test statistics of the Wilcoxon signed-rank test (normal approximation); P: Probability value associated with the within-group comparison; Rosenthal’s r: Effect size calculated from Z and n (|10| = small, |30| = medium, |50| = large).

Table 7 Comparison between groups in Profile of Mood States (Mann-Whitney and Hedges’ g)

Subscale	Moment	Group	Sample size	mean ± SD	P value	g (Hedges)
Tension	Pre-test	Control	32	8.22 ± 4.52	0.212	0.307
		Experimental	24	6.83 ± 4.36
	Post-test	Control	32	12.47 ± 2.55	0.051	0.623
		Experimental	24	10.92 ± 2.32
Depression	Pre-test	Control	32	4.00 ± 3.48	0.186	0.330
		Experimental	24	2.88 ± 3.18
	Post-test	Control	32	9.03 ± 3.48	0.194	0.399
		Experimental	24	7.75 ± 2.69
Anger	Pre-test	Control	32	11.22 ± 6.33	0.397	0.300
		Experimental	24	9.46 ± 4.95
	Post-test	Control	32	9.88 ± 4.82	0.137	0.452
		Experimental	24	7.88 ± 3.64
Vigour	Pre-test	Control	32	12.88 ± 3.20	0.526	0.112
		Experimental	24	12.54 ± 2.52
	Post-test	Control	32	6.19 ± 2.48	0.591	0.021
		Experimental	24	6.13 ± 3.38
Fatigue	Pre-test	Control	32	6.28 ± 4.03	0.303	0.222
		Experimental	24	5.33 ± 4.44
	Post-test	Control	32	4.88 ± 4.02	0.048a	0.498
		Experimental	24	3.00 ± 3.24

^aP < 0.05.

P: Probability associated with the contrast statistic (Mann-Whitney U test in intergroup comparisons); Hedges’ g: Effect size corrected for independent samples (0.20 = small, 0.50 = medium, 0.80 = large).

Table 8 Pre-post changes by group in 12-item General Health Questionnaire (Wilcoxon and Rosenthal’s r), mean ± SD

Group	Pre-test	Post-test	Z (Wilcoxon)	P value	r (Rosenthal)
Control	3.28 ± 3.05	3.03 ± 3.25	-0.122	0.903	-0.02
Experimental	2.13 ± 1.90	1.29 ± 1.60	-1.652	0.098	-0.34

Z: Test statistics of the Wilcoxon signed-rank test (normal approximation); P: Probability value associated with the within-group comparison; Rosenthal’s r: Effect size calculated from Z and n (|10| = small, |30| = medium, |50| = large).

Table 9 Comparison between groups in 12-item General Health Questionnaire (Mann-Whitney and Hedges’ g)

Moment	Group	Sample size	mean ± SD	P value	g (Hedges)
Pre-test	Control	32	3.28 ± 3.05	0.282	0.435
	Experimental	24	2.13 ± 1.90
Post-test	Control	32	3.03 ± 3.25	0.080	0.642
	Experimental	24	1.29 ± 1.60

P: Probability associated with the contrast statistic (Mann-Whitney U test in intergroup comparisons); Hedges’ g: Effect size corrected for independent samples (0.20 = small, 0.50 = medium, 0.80 = large).

Table 10 Pre-post changes by group in Pittsburgh Sleep Quality Index (Wilcoxon and Rosenthal’s r), mean ± SD

Group	Pre-test	Post-test	Z (Wilcoxon)	P value	r (Rosenthal)
Control	0.94 ± 0.76	1.03 ± 0.82	-0.615	0.539	-0.11
Experimental	1.08 ± 0.78	0.92 ± 0.72	-0.723	0.470	-0.10

Z: Test statistics of the Wilcoxon signed-rank test (normal approximation); P: Probability value associated with the within-group comparison; Rosenthal’s r: Effect size calculated from Z and n (|10| = small, |30| = medium, |50| = large).

Table 11 Comparison between groups in Pittsburgh Sleep Quality Index (Mann-Whitney and Hedges’ g)

Moment	Group	Sample size	mean ± SD	P value	g (Hedges)
Pre-test	Control	32	0.94 ± 0.76	0.411	-0.188
	Experimental	24	1.08 ± 0.78
Post-test	Control	32	1.03 ± 0.82	0.711	0.145
	Experimental	24	0.92 ± 0.72

P: Probability associated with the contrast statistic (Mann-Whitney U test in intergroup comparisons); Hedges’ g: Effect size corrected for independent samples (0.20 = small, 0.50 = medium, 0.80 = large).