A health psychologist investigated whether a cognitive bias modification (CBM) training program is effective in reducing public speaking anxiety levels in patients with social anxiety. Participants were randomly allocated to either a CBM group ( $N_a = 6$ ) or a placebo control group ( $N_b = 11$ ). Post-intervention anxiety was rated using an ordinal self-report scale. The researcher conducted a Mann-Whitney U test and calculated an observed value of $U = 13$ .

Table 1: Critical values for the Mann-Whitney U test

$N_a$	$N_b = 6$	$N_b = 7$	$N_b = 8$	$N_b = 9$	$N_b = 10$	$N_b = 11$	$N_b = 12$
$\le 0.05$ (one-tailed)
6	7	8	10	12	14	16	17

Using the critical values for the Mann-Whitney U test in Table 1, explain whether the CBM program is effective in reducing anxiety levels.

Table 1: Critical values for the Mann-Whitney U test

$N_a$	$N_b = 6$	$N_b = 7$	$N_b = 8$	$N_b = 9$	$N_b = 10$	$N_b = 11$	$N_b = 12$
$\le 0.05$ (one-tailed)
6	7	8	10	12	14	16	17

Using the critical values for the Mann-Whitney U test in Table 1, explain whether the CBM program is effective in reducing anxiety levels.

Research methods and skills

Question 27

Markscheme

Research methods and skills

Question 27

Markscheme

Research methods and skills

Question 27

Research methods and skills Questions

Research methods and skills

Question 27

Research methods and skills Questions