. Author manuscript; available in PMC: 2022 Mar 18.

Published in final edited form as: Int J Yoga Therap. 2021 Jan 1;31(1):Article_20. doi: 10.17761/2021-D-20-00004

Table 3.

Measurement Tools/Forms and Their Purposes

Measurement Tool	Standardization	Recall Period	Purpose
Patient Health Questionnaire (PHQ2/PHQ9)	Y: correlates well (r = 0.75)⁵⁰ to the Beck Depression Index (depression in the present moment); Cronbach’s alpha = 0.89⁵¹	2 wk	Depression screener used in recruitment (Visit 1)
Insomnia Severity Index (ISI)	Y	14 d	Insomnia assessment (telephone screen)
Baseline intake	N (in house)	General	To gather information on contact details; demographics (age, gender, menopause, ethnicity, language, ability to hear); substance use (alcohol, stimulants, sleeping pills, cannabis); lifestyle (disruptions to sleep, shift work, mind-body practice); and comorbidities (a diagnosis of fibromyalgia, sleep apnea, insomnia, or depression)
Sleep apnea screener (STOP-BANG)	Y: with minimal information requested, it is adequate for use in informal diagnosis; Cronbach’s alpha = 0.74⁵²	General	To predict sleep apnea at Visit 1 based on: snoring, tiredness, observations of interrupted breathing, blood pressure, BMI, age, neck circumference, and gender
Positive and Negative Affect Schedule (PANAS)	Y: Cronbach’s alpha = 0.87 (negative affect) and 0.88 (positive affect)⁵³	Moment	Assessment of mood (20 questions) before/after visit
State-Trait Anxiety Inventory Y-6 (STAI-Y6)	Y: Cronbach’s alpha = 0.89 for total scores⁵⁴	Moment	Anxiety measurement (6 questions) before/after visit
Consent form (CF)	N (in house)	General	Confirmation of participant willingness to participate in the study
Preintervention survey (PreI)	N (in house)	Moment	Assessment of participant perceptions about the intervention before they experience it
		1 d	Documentation of behavior and substance use in the last 24 hours (exercise, alcohol, caffeine intake, sleep quality, tiredness and restedness)
Generalized Anxiety Disorder Survey (GAD-7)	Y: correlates moderately with the Penn State Worry Questionnaire (r = 0.51–0.71); Cronbach’s alpha = 0.79–0.91⁵⁵	2 wk	Anxiety assessment (7 questions) at intake
Pittsburgh Sleep Quality Index (PSQI)	Y: scores ≥ 5 indicate poor sleep quality; this survey correlates with other surveys used here (PHQ-9 [0.49] and GAD-7 [0.46]); Cronbach’s alpha = 0.57⁵⁶	30 d	Sleep quality assessment at intake
Patient-Reported Outcomes Measurement Information System (PROMIS-29)	Y: Cronbach’s alpha = 0.87–0.97⁵⁷	7 d	Assessment of disturbed sleep, depression, anxiety, pain, and other health outcomes at intake
Respiratory rate (RR) monitor (Spire)	This device is popularly used and attracting research interest⁵⁸	Real-time, continuous	To gather data on breathing rate; Spire is a wearable, wireless sensor clipped to a belt
Electroencephalograph (EEG) (ProComp Infiniti device with BioGraph Infiniti software)	This device has been used in research for measurement of various physiological parameters^59,60	Real-time, continuous	To gather data on brainwave patterns and sleep
Heart rate variability (HRV; BodyGuard2)	Validated against a clinical ECG with offline R-wave detection; Bodyguard 2 has a high beat detection rate and provides accurate HRV analysis in many conditions (sitting, lying, standing, walking, etc.)⁶¹	Real-time, continuous	To gather data on HRV; the device is a wearable, wireless sensor placed on the chest
Postintervention exit survey (PE)	N (in house)	2 h	To gather perceptions of the intervention after experiencing it (credibility/acceptability/tolerability) and feedback about intervention conditions (comfort, challenges, other)