A health psychologist investigated whether a new mobile mindfulness app is effective in reducing nicotine craving intensity in smokers trying to quit. Participants were randomly allocated to either a Mindfulness App group ( $N_a = 5$ ) or a Waiting List Control group ( $N_b = 10$ ). Craving intensity was rated daily using an ordinal scale. The researcher conducted a Mann-Whitney U test and calculated an observed value of $U = 9$ .

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

$N_a$	$N_b = 5$	$N_b = 6$	$N_b = 7$	$N_b = 8$	$N_b = 9$	$N_b = 10$	$N_b = 11$	$N_b = 12$
$\le 0.05$ (one-tailed)
5	4	5	6	8	9	11	12	13

Using the critical values for the Mann-Whitney U test in Table 1, explain whether the mindfulness app is effective in reducing craving intensity scores.

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

$N_a$	$N_b = 5$	$N_b = 6$	$N_b = 7$	$N_b = 8$	$N_b = 9$	$N_b = 10$	$N_b = 11$	$N_b = 12$
$\le 0.05$ (one-tailed)
5	4	5	6	8	9	11	12	13

Using the critical values for the Mann-Whitney U test in Table 1, explain whether the mindfulness app is effective in reducing craving intensity scores.

Research methods and skills

Question 34

Markscheme

Research methods and skills

Question 34

Markscheme

Research methods and skills

Question 34

Research methods and skills Questions

Research methods and skills

Question 34

Research methods and skills Questions