The Light for the Brain Study

Global composite z-score from baseline to 8 weeks after the intervention based on the HVLT-R; BVMT-R; Psychomotor vigilance task; Trail-making tests A and B; WAIS-IV Coding, Digit Span, Block Design; D-KEFS Color-Word Inhibition, Verbal Fluency; Conners Continuous Performance Test III. Raw scores at baseline of tests within single domains were averaged and then standardized to z-scores. The mean of the z-scores was calculated, and then this composite z-score was standardized to z-scores. Follow up intervention z-scores were calculated based on differences between raw scores at baseline and raw scores at follow-up time points and divided by the standard deviation of the baseline domain z-score) within each domain, and then averaged to create follow up global composite scores. A z-score below 0 indicated poorer performance than at baseline and a z-score above 0 indicated better performance than at baseline.

Time frame: Baseline to end-of-intervention to 8 weeks after the intervention

F statistic from actigraphy was assessed as a measure of circadian activity rhythm robustness.

Time frame: Baseline to end of intervention to 8 weeks later

C-reactive protein in mg/L

Time frame: Baseline and end-of-intervention

The Center for Epidemiological Studies Depression Scale (CES-D) is a 20-item self-report instrument that measures symptoms of depressed mood over the past week.

Time frame: Baseline, Mid-intervention, End of intervention, 8 weeks later

This is a 13-item measure of fatigue.

Time frame: Baseline, mid-intervention, end of the intervention, 8 weeks later

Serum cytokine IL-6 in pg/mL

Time frame: Baseline and end-of-intervention

Total raw score for entire scale (minimum = 46, maximum = 230) with a higher score indicating greater neurobehavioral symptomatology.

Time frame: Baseline, mid-intervention, end-of-intervention, 8 weeks later

Population: Participants did not always complete this measure, which accounts for why there are sometimes fewer participants than the overall number of participants analyzed at different time points. Linear mixed models allows for missing time points.

Serum cytokine TNF-α in pg/mL

Time frame: Baseline and end-of-intervention

Population: Two participants did not provide blood samples at the end-of-intervention

This 50-item scale is a commonly used and well-validated measure of the functional status of cancer patients who have undergone BMT (SCT).

Time frame: Baseline, End of intervention, 8 weeks post-intervention

The 33-item Patient Assessment of Own Functioning Inventory (PAOFI) is a reliable and valid measure of perceptions of cognitive functioning (Bell et al., 2013; Chelune et al., 1986). Using a Likert scale from 1 (Almost Always) to 6 (Almost Never), ratings of 1-3 were scored 1 indicating impairment, and ratings from 4 to 6 were scored 0 indicating no impairment. Total impairment was calculated by summing the number of impaired items.

Time frame: Baseline, mid-intervention, end of intervention, 8 weeks after intervention

The Pittsburgh Sleep Quality Index consists of 19 self-rated items used to calculate sleep quality

Time frame: Baseline, mid intervention, end of intervention, 8 weeks later

Measure determines chronotype with a lower score indicating an evening type and a higher score indicating a morning type.

Time frame: Baseline

Treatment credibility and outcome expectancy were assessed at baseline with the mean of the first 3 items of the Credibility/Expectancy Questionnaire. Items are scored on a Likert scale from 1 to 9, and the term symptoms was replaced with thinking, memory and concentration problems. Higher scores represent greater credibility and outcome expectancy.

Time frame: Baseline

Range between 0 and 5, with 5 meaning higher treatment satisfaction

Time frame: During the 4th week of the intervention

Length of time light box has been used.

Time frame: Throughout intervention period (4 weeks)