Programa Macro

As reported previously (see Table 4.17), participants who wake during the night reported a greater frequency of overall total memory failures as well as PM failures than did those who do not.

An ANCOVA, with group (wakes during the night versus does not wake during the night) as the IV, PRMQ Total T-scores as the DV and HADS Anxiety as the covariate revealed a significant main effect of Anxiety on PRMQ Total T-scores, F (1, 476) = 43.12, p < .001, partial eta squared = .083. Notably, no significant main effect of group remained after adjusting for the effect of Anxiety, F (1, 476) = 2.09, p = .149, partial eta squared = .004.

An ANCOVA with group (wakes during the night versus does not wake during the night) as the IV, PRMQ Total T-scores as the DV and HADS Depression as the covariate revealed a significant main effect of Depression, F (1, 464) = 43.67, p < .001, partial eta squared = 0.086. As with Anxiety, the main effect of

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group was no longer significant after Depression was controlled for, F (1, 464) = 2.56, p = .110, partial eta squared = .005.

To investigate whether an effect of waking during the night on PM scores remained after anxiety was controlled for, an ANCOVA with group (wakes during the night versus does not wake during the night) as the IV, PM T-scores as the DV and HADS Anxiety as the covariate was conducted. This revealed a significant main effect of Anxiety on PM T-scores, F (1,476) = 43.12, p < .001, partial eta squared = .083.

Of interest, no significant main effect of group remained after adjusting for the effect of anxiety, F (1,476)

= 2.80, p = .095, partial eta squared = .006.

ANCOVA with group (wakes during the night versus no) as the IV, PM Total T-scores as the DV and HADS Depression as the covariate revealed a significant main effect of HADS Depression on PM T-scores, F (1, 464) = 36.69, p < .001, partial eta squared = .073. It also revealed that no significant main effect of group remained after adjusting for the effect of Depression, F (1,464) = 3.05, p = .081, partial eta squared = .007.

Since there were no significant difference in RM scores between those who wake during the night and those who do not, it was not necessary to carry out an ANCOVA with those variables.

As shown in Table 4.17, those participants who wake earlier than intended reported a greater frequency of memory failures across the PRMQ scales. Thus, separate ANCOVAs controlling for the influence of self-reported anxiety and depression respectively were carried out to investigate if the between groups differences in PRMQ T-scores remained adjusting for HADS anxiety and depression scores.

An ANCOVA with group (wakes earlier than intended versus does not wake earlier than intended) as the IV, PRMQ Total T-scores as the DV and HADS Anxiety as the covariate revealed a significant main effect of Anxiety, F (1, 474) = 36.41, p < .001, partial eta squared = 0.71 and revealed that the main effect of group remained significant after adjusting for the influence of Anxiety, F (1, 474) = 6.43, p = .012, partial eta squared = .013. However, it should be noted that the assumption of homogeneity of variance was violated, F(1, 475) = 3.94, p = .048.

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Table 4.18: Unadjusted and adjusted mean PRMQ T-scores of sleep variable subgroups following ANCOVA controlling for HADS Anxiety and Depression.

Wakes during the night? Wakes earlier than intended Naps during the day Takes medication/

alcohol to help sleep

Yes No Yes No Yes No Yes No

PRMQ Total Scale T-Scores

Unadjusted mean 54.50 57.89 53.06 56.67 53.15 56.08 53.02 55.83

Adjusted mean

(controlling for HADS-A)

54.62 56.76 53.73 55.99 53.48 55.86 54.37 54.99

Unadjusted mean 54.43 58.05 53.36 56.36 53.18 55.93 52.78 55.28

Adjusted mean

(controlling for HADS-D)

54.52 57.03 53.92 55.73 53.63 55.63 53.93 55.00

PRMQ PM subscale T-Scores

Unadjusted mean 52.16 56.00 50.62 54.49 51.03 53.60 50.80 52.98

Adjusted mean

(controlling for HADS-A)

52.28 54.84 51.30 53.79 51.37 53.37 52.21 52.63

Unadjusted mean 52.08 56.00 50.82 54.23 51.07 53.41 50.59 52.90

Adjusted mean

(controlling for HADS-D)

52.17 55.02 51.35 53.63 51.50 53.12 51.69 52.63

PRMQ RM subscale T-Scores

Unadjusted mean n/a n/a 53.43 56.18 53.23 55.95 53.40 55.16

Adjusted mean

(controlling for HADS-A)

n/a n/a 53.95 55.64 53.49 55.78 54.44 54.90

Unadjusted mean n/a n/a 53.76 55.86 53.23 55.87 53.15 55.17

Adjusted mean

(controlling for HADS-D)

n/a n/a 54.25 55.31 53.61 55.61 51.15 54.92

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An ANCOVA with group (wakes earlier than intended versus does not wake earlier than intended) as IV, PRMQ Total T-scores as the DV and HADS depression as the covariate revealed a significant main effect of Depression, F (1, 463) = 39.05, p <.001, partial eta squared = .078. The main effect of group was remained significant after Depression was controlled for, F (1, 463) = 4.09, p = .044, partial eta squared

= .009. It is, however, important to note that that the assumption of homogeneity of variance was violated, F(1, 464) = 5.016, p = .026, with the larger variance associated with the group who report waking earlier than expected. Consequently, there is the increased risk of incorrectly rejecting the null hypothesis, so the results of this ANCOVA should be interpreted with caution.

ANCOVA with group (wakes earlier than intended versus does not wake earlier than intended) as the IV, PM T-scores as DV and HADS Anxiety as the covariate revealed a significant main effect of Anxiety, F (1,474) = 35.80, p <.001, partial eta squared = .070. It also revealed that the main effect of group remained significant after Anxiety was controlled for, F (1, 474) = 7.31, p = .007, partial eta squared = .015. ANCOVA with group (wakes earlier than intended versus does not wake earlier than intended) as the IV, PM T-scores as the DV and HADS Depression as the covariate revealed a significant main effect of Depression, F (1,463) = 31.84, p <.001, partial eta squared = .064. The main effect of group remained significant after depression was controlled for, F (1, 463) = 6.02, p = .015, partial eta squared = .013.

ANCOVA with group (wakes earlier than intended versus does not wake earlier than intended) as the IV, RM T-scores as the DV and HADS Anxiety as the covariate revealed a significant main effect of Anxiety, F (1,474) = 25.69, p <.001, partial eta squared = .051 and it revealed that the main effect of group remained significant after Anxiety was controlled for, F (1, 474) = 4.05, p = .045, partial eta squared = .008. The assumption of homogeneity of variance was violated, Levene’s F(1,475) = 3.99, p = .046, so results should be interpreted with some caution. An ANCOVA with the same IV and DV but with HADS Depression as the covariate revealed a significant main effect of Depression, F (1,463) = 33.79, p <.001, partial eta squared = .068. Of interest, the main effect of group was no longer significant after controlling for depression, F (1, 463) = 1.61, p = .205, partial eta squared = .003.

To investigate whether the effects of napping during the day on PRMQ remained significant after controlling for the influence of HADS anxiety and HADS depression, ANCOVA was first conducted with group (takes naps during the day versus does not takes naps during the day) as the IV, PRMQ Total T-scores as the DV, and HADS Anxiety as the covariate. Results showed a significant main effect of HADS Anxiety, F (1,471) = 44.00, p <.001, partial eta squared = .085. The main effect of group remained significant after controlling for Anxiety, F (1, 471) = 7.21, p = .008, partial eta squared = .015. ANCOVA with the same IV (takes naps during the day versus does not takes naps during the day), PRMQ Total T-scores as the DV, but this time with HADS Depression as the covariate showed a significant main effect

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of Depression, F (1, 461) = 41.19, p <.001, partial eta squared = .082. The ANCOVA also revealed that the main effect of napping during the day remained significant after the effects of Depression was accounted for, F (1, 461) = 5.04, p =.025, partial eta squared = .011.

ANCOVA with group (takes naps during the day versus does not takes naps during the day) as the IV, PM T-scores as the DV, and HADS Anxiety as the covariate showed a significant main effect of Anxiety, F (1,471) = 43.82, p <.001, partial eta squared =.085. The main effect of group remained significant after adjusting for the influence of Anxiety, F (1, 471) = 4.73, p =.030, partial eta squared = .010. ANCOVA with the same IV (takes naps during the day versus does not takes naps during the day), and PM T-scores as the DV, but with HADS Depression as the covariate showed a significant main effect of Depression, F (1, 461) = 35.45, p <.001, partial eta squared =.071. However, the main effect of group was no longer significant after adjusting for the influence of Depression, F (1, 461) = 2.96, p =.086, partial eta squared

= .006.

ANCOVA with group (takes naps during the day versus does not takes naps during the day) as the IV, RM T-scores as the DV, and HADS Anxiety as the covariate showed a significant main effect of Anxiety, F (1,471) = 30.58, p <.001, partial eta squared =.061 and the main effect of group remained significant after adjusting for the influence of Anxiety, F (1, 471) = 7.72, p =.006, partial eta squared = .016. ANCOVA with the same IV (takes naps during the day versus does not takes naps during the day) and DV (RM T-scores) but with HADS Depression as the covariate showed a significant main effect of Depression, F (1,461) = 33.66, p <.001, partial eta squared =.068. of interest, the main effect of group remained significant after adjusting for the influence of Depression, F (1,461) = 5.83, p =.016, partial eta squared = .012.

ANCOVA with group (takes alcohol or medication to help sleep versus does not), PRMQ Total T-score as the DV and HADS Anxiety as the covariate revealed a significant main effect of Anxiety, F (1,473) = 44.41, p <.001, partial eta squared = .086. The main effect of group was, however, no longer significant after anxiety was controlled for, F (1,473) = .306, p = .580, partial eta squared = .001. ANCOVA with the same IV (takes alcohol or medication to help sleep versus does not) and DV (PRMQ Total T-scores) but with HADS Depression as the covariate revealed a significant main effect of Depression, F (1,462) = 36.06, p

<.001, partial eta squared = .072. As with Anxiety, the effect of group was no longer significant following adjustment for Depression, F (1,462) = .883 p = .348, partial eta squared = .002.

ANCOVA with group (takes alcohol or medication to help sleep versus does not) as the IV, PM T-scores as the DV, and HADS anxiety as covariate revealed a significant main effect of Anxiety, F (1,473) = 46.17, p

<.001, partial eta squared = .089. The main effect of taking alcohol or medication to help sleep was, however, no longer significant once self-reported anxiety was controlled for, F (1,473) = .128, p =.721, partial eta squared = .000. ANCOVA with the same IV (takes alcohol or medication to help sleep versus

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does not) and DV (PM T-scores) but Depression as the covariate revealed a significant main effect of Depression, F (1,462) = 30.05, p <.001, partial eta squared =.061. The effect of group was, however, no longer significant following adjustment for Depression, F (1,462) = .619, p = .432, partial eta squared = .001.

ANCOVA with group (takes alcohol or medication to help sleep versus does not) as the IV, RM T-scores as the DV, and HADS Anxiety as covariate revealed a significant main effect of Anxiety, F (1, 473) = 30.08, p

<.001, partial eta squared = .060. The main effect of was no longer significant once self-reported anxiety was controlled for, F (1, 473) = .19, p =.662, partial eta squared = .000. ANCOVA with the same IV (takes alcohol or medication to help sleep versus does not) and DV (RM T-scores) but depression as the covariate revealed a significant main effect of depression, F (1,462) = 31.16, p <.001, partial eta squared = .063. As with HADS Anxiety, the effect of group was no longer significant following adjustment for Depression, F (1, 462) = .563, p = .464, partial eta squared = .001.

Partial correlations (1-tailed) controlling for HADS scores were carried out to see if the associations between self-reported memory and average hours slept remained after self-reported depression and anxiety were controlled for. Results showed that the correlation between PRMQ Total T-scores and average hours slept were no longer significance after HADS Total score was controlled, r = .041, p = .181.

The correlation between PM T-scores and average hours slept similarly was no longer significance once HADS Total score was controlled, r = .051, p = .132. Finally, there was no significant association between RM T-scores and average hours slept after controlling for HADS Total scores, r = .021, p = .325.

However, in order to see whether depression and anxiety differentially influence the correlation between average number of hours of sleep and PRMQ T-scores, partial correlations were next carried out, controlling for the HADS Anxiety and HADS Depression subscales separately. While results still showed a lack of a significant relationship between average number of hours of sleep and PRMQ Total, PM and RM scale T-scores after Anxiety was controlled for, the relationship between average number of hours of sleep and PM T-scores remained significant after depression was controlled for, r = .082, p = .040.

4.4.4.7 Impact of alcohol consumption on PRMQ: In relation to PRMQ scores, there was a significant