Table A7: GRADE Evidence Table for Long-Term Oxygen Therapy and Health-Related Quality of Life, Severe Hypoxemia^*.

LTOT Only: Health-Related Quality of Life
Population: Patients With COPD
Outcomes	Illustrative Comparative Risks (95% CI)	Relative Effect (95% CI)	No. of Participants (studies)	Quality of Evidence (GRADE)	Comments
	Assumed Risk Corresponding Risk
CRQ†	Meta-analysis not performed	Not estimable	157 (2 studies)	⊕ ⊕ Low§,║,¶	LTOT only Observational
SGRQ‡	Meta-analysis not performed	Not estimable	19 (1 study)	⊕ Very low#	LTOT only Observational

^*Abbreviations: CI, confidence interval; COPD, chronic obstructive pulmonary disease; CRQ, Chronic Respiratory Questionnaire; LTOT, long-term oxygen therapy; no., number; SGRQ, St. George’s Respiratory Questionnaire.

^†Eaton et al (44) and Crockett et al (45).

^‡Okubadejo et al (47).

^§Ambulatory oxygen provided in 1 study. (did not contribute to GRADE)

^║Confounders not accounted for. (did not contribute to GRADE)

^¶CRQ was characterized differently for each study. (did not contribute to GRADE)

^#Sparse data. (−1)