LCQ LCQ Research and Comparative Studies 1 — Questions and Answers
Question 1: The LCQ has been used as a primary or secondary endpoint in clinical trials of which class of antitussive medication?
- Proton pump inhibitors only
- P2X3 receptor antagonists such as gefapixant (Correct answer)
- Antihistamines only
- Oral antibiotics
Correct answer: P2X3 receptor antagonists such as gefapixant
The LCQ has been used as a key endpoint in clinical trials of P2X3 receptor antagonists like gefapixant for refractory chronic cough.
Question 2: Compared to the Cough Quality of Life Questionnaire (CQLQ), the LCQ is considered:
- Longer and less practical for routine clinical use
- Shorter and more practical while retaining good psychometric properties (Correct answer)
- Equivalent in length and scope
- Less validated and rarely used in research
Correct answer: Shorter and more practical while retaining good psychometric properties
The LCQ (19 items) is shorter than the CQLQ (28 items) while maintaining strong psychometric properties, making it more practical for clinical settings.
Question 3: In comparative research, the LCQ total score has been shown to correlate moderately with which objective cough measure?
- FEV1/FVC ratio
- 24-hour cough frequency count (Correct answer)
- Serum eosinophil count
- Peak expiratory flow rate
Correct answer: 24-hour cough frequency count
The LCQ total score shows moderate correlation with 24-hour objective cough frequency counts, supporting its construct validity as a cough burden measure.
Question 4: Research has demonstrated that the LCQ is responsive to change, meaning:
- It measures the same score repeatedly regardless of treatment
- It detects statistically and clinically meaningful score changes following effective treatment (Correct answer)
- It is only useful for baseline measurements
- It cannot detect improvement, only worsening
Correct answer: It detects statistically and clinically meaningful score changes following effective treatment
Responsiveness is a key psychometric property; LCQ studies demonstrate it can detect meaningful score improvements following successful treatment.
Question 5: The LCQ has been validated for use in which of the following disease populations beyond idiopathic chronic cough?
- Acute bronchitis only
- Bronchiectasis, COPD, interstitial lung disease, and asthma (Correct answer)
- Pediatric asthma only
- Post-thoracic surgery patients only
Correct answer: Bronchiectasis, COPD, interstitial lung disease, and asthma
The LCQ has been validated across multiple respiratory conditions including bronchiectasis, COPD, interstitial lung disease, and asthma.
Question 6: In a systematic review context, the LCQ is considered a preferred outcome measure for chronic cough trials because:
- It is the only available cough quality of life tool
- It has the strongest evidence base for reliability, validity, and responsiveness among cough-specific PROs (Correct answer)
- It requires no patient training to complete
- It was endorsed by the FDA as the only acceptable endpoint
Correct answer: It has the strongest evidence base for reliability, validity, and responsiveness among cough-specific PROs
The LCQ has the most extensive evidence base for psychometric quality among chronic cough-specific PROs, making it the preferred measure in systematic reviews and meta-analyses.
LCQ LCQ Research and Comparative Studies 1
The LCQ has been used as a primary or secondary endpoint in clinical trials of which class of antitussive medication?