St. George’s Respiratory Questionnaire

Abstract

The St. George’s Respiratory Questionnaire (SGRQ) is a widely recognized, standardized, and disease-specific Patient-Reported Outcome (PRO) measure used primarily in individuals diagnosed with Chronic Obstructive Pulmonary Disease (COPD). Its main function is to quantify the degree of functional limitation experienced during daily activities and to assess the impact of the respiratory condition on the patient’s overall Health-Related Quality of Life (HRQoL). The SGRQ yields a total score where higher scores indicate greater impairment and increased limitations in health status.

Keywords

St. George’s Respiratory Questionnaire, SGRQ, COPD, Respiratory Disease, Quality of Life, Functional Limitation, Activities of Daily Living, Patient-Reported Outcome, Health Status.

Authors

Jones PW (1991), Jones P (2012), KNGF-richtlijn COPD (2008)

Purpose

The primary purpose of the SGRQ is to provide a robust, standardized assessment of the perceived health and well-being of patients suffering from chronic airflow limitation, particularly those with COPD. It is designed to capture the subjective burden of the disease, moving beyond simple physiological measures to understand how respiratory symptoms affect a patient’s daily functioning and emotional state.

The instrument is highly sensitive to change, making it invaluable for measuring the efficacy of clinical interventions, rehabilitation programs, and pharmacological treatments in clinical trials and routine care. By quantifying the impact on daily life, the SGRQ helps clinicians and researchers identify aspects of life most influenced by the chronic condition.

Construct

The SGRQ measures the construct of Health-Related Quality of Life (HRQoL) specifically tailored for respiratory conditions. It is typically divided into three core domains, which together capture the multifaceted nature of living with a chronic lung disease:

• Symptoms: Measures the frequency and severity of respiratory symptoms such as cough, phlegm, wheeze, and breathlessness.
• Activity: Assesses the limitations imposed by the disease on physical activities, ranging from moderate exercise to simple daily tasks like dressing or walking short distances.
• Impact: Evaluates the psychosocial and emotional consequences of the disease, including distress, sleep disturbance, feelings of frustration, and impact on social life and work.

These domains combine to produce a total score reflecting overall health impairment. The SGRQ is recognized for its ability to track changes in patient status over time, making it a critical tool in longitudinal studies of respiratory health.

Validity

The SGRQ exhibits strong evidence of construct validity, demonstrated by its high correlations with other measures of respiratory health status, lung function (such as FEV1), and exercise capacity. Studies consistently show that the SGRQ total score significantly differentiates between groups of patients with varying disease severity, confirming its ability to accurately measure the intended construct.

Furthermore, criterion validity is supported by its correlation with patient global assessments of change in health status following therapeutic interventions. The SGRQ has been widely validated across diverse international populations and languages, confirming its cross-cultural applicability and robustness as a health outcome measure.

Reliability

The reliability of the SGRQ is well-established through extensive psychometric analysis. Internal consistency, measured typically using Cronbach’s alpha, is consistently high (often exceeding 0.90 for the total score and generally above 0.80 for the individual domain scores), indicating that the items within the scale are highly correlated and measure the same underlying construct.

Test-retest reliability is also strong, confirming the stability of the measure over short periods in clinically stable patients. The responsiveness of the SGRQ—its ability to detect clinically meaningful changes following treatment—is considered excellent, exceeding that of many generic quality of life instruments in respiratory populations.

Factor Analysis

Early factor analysis of the SGRQ confirmed its intended multi-dimensional structure. The results typically support the extraction of the three main factors: Symptoms, Activities, and Impact. This factorial structure ensures that each domain contributes uniquely to the overall assessment of HRQoL, preventing redundancy and allowing for targeted interpretation of patient difficulties.

The clarity of the factor structure has been maintained across numerous translations and cultural adaptations, reinforcing the scale’s fundamental design. The revised versions, such as the SGRQ-C, continue to rely on this established factor model for scoring and interpretation.

Instrument

Test Type: Questionnaire (Self-Administered Patient-Reported Outcome)

Format: Standardized, disease-specific measure

Language Available: English, Dutch (Nederlandse versie: KNGF-richtlijn COPD), and numerous other international translations.

Population Group: Clinical population with chronic respiratory disease (primarily COPD and asthma).

Age Group: Adults, Elderly

Population Details: Individuals suffering from conditions affecting the Circulation and respiratory system or Lung diseases (Thorax/abdomen/organs).

Test Methodology: The scale requires patients to respond to items related to their symptoms, physical activities, and psychosocial impact. Scores are weighted and calculated to produce domain scores and a total score (0 to 100), where 0 represents the best health status and 100 the worst.

Keywords

SGRQ-C, Psychometrics, Respiratory Symptoms, Activity Limitation, Participation, Personal Factors, Chronic Airflow Limitation, Health Status Measurement.

Authors

Author ORCID Identifier: Not provided in source material.

Affiliation Email addresses: Not provided in source material.

Correspondence Address: Not provided in source material.

Permissions & Fee and Test Year

The original version of the SGRQ was developed by PW Jones in 1991. The revised version, SGRQ-C, was developed by P Jones in 2012. The Dutch translation was developed following the KNGF-richtlijn COPD in 2008. The scale is typically managed under licensing agreements, and permission for use, especially in commercial research, may require a fee.

Reference’s

The following supporting documentation is available:

• The original Dutch Explanation Form (Toelichtingsformulier) can be downloaded here: SGRQ-form.pdf
• The Measurement Instrument (Meetinstrument) used in the KNGF context can be downloaded here: SGRQ-meetinstr-KNGF.pdf
• The English Manual for the revised SGRQ-C can be downloaded here: SGRQ-C-handl-Eng.pdf
• The English Manual for the original SGRQ can be downloaded here: SGRQ-handl-Eng.pdf
• Jones PW, Quirk FH, Baveystock CM, Littlejohns P. A self-complete measure of health status for chronic airflow limitation. The St. George’s Respiratory Questionnaire. Am Rev Respir Dis 1992; 145: 1321–1327.
• Jones P. St. George’s Respiratory Questionnaire. COPD: Journal of Chronic Obstructive Pulmonary Disease 2012; 9(4): 436–437.

Items of the St. George’s Respiratory Questionnaire

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

The specific text of the scale items was not provided in the original source content. The source provided links to the measurement instrument and manuals, but not the direct item list.