Patients' perspectives on how idiopathic pulmonary fibrosis affects the quality of their lives

Table 3 Comparison of the content/domain coverage of the CRQ-SAS, SF-36, SGRQ, and WHOQOL-100 with the domains identified in our conceptual framework

	Number of Items
Domains in conceptual framework	CRQ-SAS k = 20†	SF-36 k = 36†	SGRQ k = 50†	WHOQOL-100 k = 100†
1. IPF Symptoms	5‡	14§	33 ∥	0
2. IPF Therapy	0	0	4**	0
3. Sleep	0	0	0	4
4. Exhaustion	4	4¶	2	4¶
5. Forethought	0	0	2	0
6. Employment and Finances	0	0	1	8
7. Dependence	0	0	0	0
8. Family	0	1	0	3
9. Sexual Relations	0	0	0	4
10. Social Participation	0	2	2	9
11. Mental and Spiritual Well-being	11	8	6	12
12. Mortality	0	0	0	0

† These columns show how each item from the CRQ-SAS, SF-36, SGRQ, and WHOQOL-100 maps onto the domains identified in this study; ‡One item mentions cough; §These items address the impact of physical health on activities but do not specifically address symptoms (e.g., breathlessness and cough); ∥Two items are about wheezing and two are about "attacks of chest trouble", making them irrelevant for patients with IPF; ¶These items ask about energy level and fatigue, but none of them pertain to exhaustion; **Items do not pertain specifically to IPF therapy; CRQ-SAS = Chronic Respiratory Questionnaire Self-Administered Standardized Format; SF-36 = Medical Outcomes Study Short-Form 36-item Instrument; SGRQ = St. George's Respiratory Questionnaire; WHOQOL-100 = World Health Organization 100-item Quality of Life Instrument.