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The SGRQ (St George’s Respiratory Questionnaire) is a 50-item, disease-specific questionnaire that measures how obstructive airways disease affects a person’s overall health, daily life and perceived well-being. Scores run from 0 to 100, and a higher score means more limitation. It is a patient-reported instrument, not a lung-function test, and this page is general reference information, not medical advice.
Short answer
The SGRQ is a patient-completed health-status questionnaire developed at St George’s, University of London, and used mainly in asthma and COPD research and clinical trials. It returns a total score and component scores from 0 (no impairment) to 100 (maximum impairment). It is usually scored by computer, takes about 8 to 15 minutes to complete, and is free for clinicians but licensed for commercial organisations.
Definition and scope
According to the American Thoracic Society’s description of the instrument, the SGRQ is a disease-specific tool for obstructive airways disease. It has 50 items in two parts and three components:
- Symptoms (Part 1): frequency and severity of respiratory symptoms.
- Activities (Part 2): activities that are limited by breathlessness.
- Impacts (Part 2): social functioning and psychological disturbance resulting from the airways disease.
The developers describe the 50 items as carrying 76 weighted responses, which is why the questionnaire is best scored by computer rather than by hand. It was developed and validated in asthma and COPD, and has since been applied to several other lung conditions. The original paper is Jones PW, Quirk FH, Baveystock CM, Littlejohns P. Am Rev Respir Dis 1992;145:1321-1327.
How it is used in practice
Recall periods
The Symptoms component can be given a recall period of 1, 3 or 12 months; the ATS description notes that the 3-month and 12-month versions perform best. The Impacts items refer to the person’s current state.
Scoring
Each component and the total are expressed on a 0 to 100 scale, where higher means more limitation. Because of the weighted responses, researchers use the developer’s computer scoring calculator rather than summing answers manually. The ATS page states that the licence, the Excel scoring calculator and translations are obtained through [email protected].
Interpreting change: the MCID
The developers recommend a 4-unit difference as the minimal clinically important difference (MCID) when comparing group means. Their supporting evidence includes patient-judgement estimates of 3.9 and 4.1 and a clinician estimate of 3.9, and a responder-analysis odds ratio that was consistent across thresholds from 1.5 to 8.0. Other published estimates differ, for example 7 to 8 units in one study (Welling) and 3.1 when derived from the Chronic Respiratory Questionnaire. The 4-unit figure is a group-mean benchmark; it is not a threshold that proves an individual patient has improved. For the difference between anchor-based and distribution-based approaches, see MCID estimation methods, and for measurement error see minimal detectable change.
Versions and related concepts
| Version | What the developer states |
|---|---|
| SGRQ (original) | 50 items; developed and validated in asthma and COPD, also used in several other lung conditions. |
| SGRQ-C | A COPD-specific version derived from COPD data only. |
The developer’s permission page covers the SGRQ, the SGRQ-C and a further version (SGRQ-I), and the same group publishes sister instruments such as the AQ20 and LVD36. Check which version a protocol or a published result used before comparing scores across studies.
Where it matters for labs, clinics and trials
The SGRQ is a clinical outcome assessment: a measure of how a patient feels or functions, used as a trial endpoint alongside objective measures such as spirometry or body plethysmography. Teams that plan to use it should work through a short checklist, each point drawn from the developer and ATS descriptions above:
- Version: SGRQ or SGRQ-C, and the same one throughout the study.
- Recall period: 1, 3 or 12 months for the Symptoms component, fixed in the protocol.
- Licence: clinicians may use it without charge; commercial organisations pay a licence fee, arranged through the developer.
- Scoring: use the developer’s computer or Excel calculator because of the weighted responses.
- Translation: request validated translations from the developer.
- Interpretation: pre-specify the MCID used (the developer recommends 4 units for means) and report responders as well as mean change.
For broader guidance on selecting and validating instruments of this kind, see choosing and validating a patient-reported outcome measure.
Common misunderstandings
- Higher is not better. On the SGRQ a higher score means more limitation, so a falling score indicates improvement.
- It is not a diagnostic test. It measures the impact of airways disease on the person, not the presence or severity of airflow obstruction.
- The MCID is not an individual cut-off. The 4-unit value is recommended for comparing means between groups or over time.
- It is not free for every user. Clinical use is free; commercial organisations are licensed.
FAQ
What does SGRQ stand for?
St George’s Respiratory Questionnaire, developed at St George’s, University of London.
What is a good SGRQ score?
Scores range from 0 to 100 and lower scores mean less impairment. There is no single “good” value; interpretation depends on the population and on change over time against the MCID.
How long does the SGRQ take?
The developers state about 8 to 15 minutes.
Is the SGRQ only for COPD?
No. The original was developed and validated in asthma and COPD and used in other lung conditions; the SGRQ-C is the version derived from COPD data only.
Sources
- American Thoracic Society, St George’s Respiratory Questionnaire (SGRQ), read 2026-11-07.
- St George’s, University of London, St George’s Respiratory Questionnaire, read 2026-11-07.
- St George’s, University of London, SGRQ minimum clinically important difference, read 2026-11-07.
- Jones PW, Quirk FH, Baveystock CM, Littlejohns P. A self-complete measure of health status for chronic airflow limitation. Am Rev Respir Dis 1992;145:1321-1327.
