4. Relevant trial‐reported ANOVAs compared to posthoc review author calculations.

Cross‐over trial	Outcome	Description of ANOVA strategy	ANOVA results	Correlation coefficient (CC)	Estimates of P values by CC (see Unit of analysis issues)
Sadeghniiat‐Haghighi 2011	Sleepiness on‐shift overall	"A two‐factor repeated measurement ANOVA was used. Factors: 1) treatment; 2) time (of night measurement) P values were corrected for sphericity (using the Huynh‐Feldt coefficient). Significance was defined at P < 0.05."	Period 1 : Time of night measurement × Treatment: (F = 8.76; P < 0.001) Time of night measurement: (F = 40.98; P < 0.001) Period 2 : Time of night measurement × Treatment: (F = 5.124, P < 0.01) Time of night measurement: (F = 9.872; P < 0.001)	0.9 0.7 0.0	< 0.0001 < 0.0001 < 0.0001
Karchani 2011	Sleepiness on‐shift overall	"Using the paired t‐test, we compared subjective sleepiness between two conditions (with bright light and with normal light). A repeated measure ANOVA showed interaction between independent variables in this study. The level of significance was defined at P < 0.05. (examined treatment effect, carry‐over effect, and period effect)."	The findings for treatment effect, period effect and carry‐over effect of the study population: Treatment effect: t df P value –21.95 89 0.001	0.9 0.7 0.0	< 0.0001 < 0.0001 < 0.0001
Lowden 2004	Sleep efficiency (actigraph)	"The data obtained during night work were submitted to ANOVA for repeated measures, with correction for unequal variances according to Huynh and Feldt (Huynh 1976). The two‐way ANOVA included the factors of condition (Bright light/Normal light) and day (15 examined night shifts). A third factor, time of day, was added for variables with several measures during 1 day (for melatonin and KSS). A fourth factor, week (three studied night work weeks), was added to give a more detailed analysis of KSS ratings. Posthoc mean comparisons were carried out with contrasts. KSS ratings during the night shift week (means of 3 weeks): As some workers showed missing data on Fridays, this day was omitted from the analysis. To reflect the many data points, a four‐way analysis of variance including the factors of condition, week (3 weeks), night (night 1–4 of each week) and time of day, were used."	Condition: NS (no P value reported) Cond./Night Interaction: NS	0.9 0.7 0.0	< 0.0001 0.02 0.20
	Total sleep time‐main sleep (bed time; final awakening)		Condition: NS (no P value reported) Cond./Night Interaction: NS	0.9 0.7 0.0	0.01 0.14 0.43
	Total sleep time‐24‐hr sleep		Condition: (P < 0.05) Cond./Night Interaction: NS	0.9 0.7 0.0	< 0.0001 0.04 0.24
	Sleepiness on‐shift KSS (overall)		Sleepiness: "No main effects were obtained except for time of day showing an increase of sleepiness throughout the night shift (F = 36.46; P = 0.0001; df = 3/45). A significant interaction was obtained (Fig. 2) for the interaction of condition, night and time (F = 2.39; P = 0.0365; df = 9/135). Sleepiness was significantly reduced in the bright light condition at 02:00 hours on Tuesday; at 04:00 hours on Monday, Tuesday and Thursday; and at 06:00 hours on Tuesday and Thursday as shown by the posthoc mean comparisons. The reduction of sleepiness in the bright light condition was further emphasised by the significant interaction of condition and time of day (F = 3.07; P = 0.0429; df = 3/45). The interaction of week + light was insignificant."	0.9 0.7 0.0	< 0.0001 0.06 0.31
	Sleepiness on‐shift KSS (postintervention)			0.9 0.7 0.0	< 0.0001 0.09 0.35
Smith 2007	Sleepiness on‐shift – Reaction time – postintervention (03:00 and 04:00 and 05:00 and 06:00)	"For each of the dependent variables, a set of 2 x 2 repeated measures ANOVAs were carried out. In order to control for interindividual variability in baseline performance, scores for all four dependent variables (response speed, M10%RT, lapse frequency and subjective sleepiness) were expressed relative to the baseline test score obtained at 00:00 hours, calculated by subtracting the 00:00 hours’ value from each hourly score. That is, 00:00 hours scores were zeroed and subsequent scores were relative to this point. Relative scores at each hour of shift were then averaged to obtain the mean relative performance across participants. In order to analyse specific time differences in the dependent variables after the nap, parallel ANOVAs were carried out with different levels entered for the time factor (i.e. before nap and 03:00 hours; before nap and 04:00 hours; before nap and 05:00 hours; before nap and 06:00 hours). Before‐nap mean scores were calculated from a combined average of 00:00, 01:00 and 02:00 hours data. As the aim was to compare nap and no‐nap conditions after the nap, the statistics of interest were the nap × time interactions. Significant interactions were observed for response speed at 04:00 and 06:00… and for subjective sleepiness at 03:00 and 04:00. … Participants therefore had faster reaction times, and less subjective sleepiness, after the nap."	Before nap vs 06:00 Nap: P = 0.002 Time: P = 0.011 N x T : P = 0.012	0.9 0.7 0.0	< 0.0001 0.02 0.21
	Sleepiness on‐shift – Subjective sleepiness score – postintervention (03:00 and 04:00 and 05:00 and 06:00)		Before nap vs 06:00 Nap: P = 0.16 Time: P = 0.201 N x T : P = 0.095	0.9 0.7 0.0	< 0.0001 < 0.0001 0.05

df: Degrees of Freedom

KSS: Karolinska Sleepiness Scale

M10%RT: Mean of the fastest 10% reaction time

NS: Not Significant

RT: Reaction Time