Menstrual cycle related depressive symptoms and their diurnal fluctuations – an ambulatory assessment study

BMC Women's Health

Table 3 Reliability and factor loadings of within-day assessments (based on ω)

Symptom	Overall estimate ω	Morning	Afternoon	Evening
PHQ-1: Diminished interest	0.60 [0.57–0.64]	0.51	0.76	0.46
PHQ-2: Depressed mood	0.69 [0.66–0.72]	0.57	0.79	0.59
PHQ-4: Low energy	0.60 [0.57–0.64]	0.42	0.81	0.49
PHQ-5: Changed appetite	0.70 [0.67–0.73]	0.64	0.79	0.54
PHQ-6: Feeling worthless	0.69 [0.66–0.72]	0.54	0.80	0.60
PHQ-7: Concentration problems	0.65 [0.62–0.68]	0.61	0.67	0.57
PHQ-8: Reduced movement/ Restlessness	0.56 [0.52–0.61]	0.58	0.55	0.53
PHQ-9: Suicidal ideation	0.61 [0.58–0.65]	0.55	0.68	0.54
Sum score	0.78 [0.76–0.80]	0.68	0.86	0.67

Note: ω = reliability estimates indicating whether depressive symptoms follow similar trajectories across the cycle when measured on three different daily occasions. Higher ω indicates higher internal consistency. Reliability estimates range between 0 and 1 and can be interpreted as no reliability (0.0–0.1), slight (0.11–0.4), fair (0.41–0.6), moderate (0.61–0.8) and substantial (0.81–1.0) reliability [44, 45]

ISSN: 1472-6874