Reliability and validity of a korean version of the leicester cough questionnaire.
OBJECTIVE
There are no specific tools for measurement of the severity of chronic cough in Korea. We developed a Korean version of the Leicester Cough Questionnaire (LCQ) and tested its scaling and clinical properties.


METHODS
The LCQ was adapted for Korean conditions following a forward-backward translation procedure. All patients referred to chronic cough clinics at 5 university hospitals between May 2011 and October 2013 completed 2 questionnaires, the LCQ and the Short-Form 36 (SF-36), upon presentation and completed the LCQ and the Global Rating of Change (GRC) upon follow-up visits after 2 or 4 weeks. Concurrent validation, internal consistency, repeatability, and responsiveness were determined.


RESULTS
For the concurrent validation, the correlation coefficients (n=202 patients) between the LCQ and SF-36 varied between 0.42 and 0.58. The internal consistency of the LCQ (n=207) was high for each of the domains with a Cronbach's alpha coefficient of 0.82-0.94. The repeatability of the LCQ in patients with no change in cough (n=23) was high, with intra-class correlation coefficients of 0.66-0.81. Patients who reported an improvement in cough (n=30) on follow-up visits demonstrated significant improvement in each of the domains of the LCQ.


CONCLUSIONS
The Korean version of the LCQ is a valid and reliable questionnaire for measurement of the severity of cough in patients with chronic cough.
Department of Internal Medicine, Kangwon National University Hospital, Chuncheon, Korea.
Jae Woo
JW
Kwon
Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea.
Ji Yong
JY
Moon
Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.; Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Sae Hoon
SH
Kim
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Woo Jung
WJ
Song
Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul, Korea.
Min Hye
MH
Kim
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Min Gyu
MG
Kang
Department of Internal Medicine, Armed Forces Capital Hospital, Seongnam, Korea.
Kyung Hwan
KH
Lim
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
So Hee
SH
Lee
Department of Internal Medicine, Gachon University Gil Medical Center, Gachon University, Incheon, Korea.
Sang Min
SM
Lee
Division of Allergy, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Jin Young
JY
Lee
Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Hyouk Soo
HS
Kwon
Department of Internal Medicine, Pogunhan Mom Hospital, Seoul, Korea.
Kyung Mook
KM
Kim
Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea.
Sang Heon
SH
Kim
Department of Internal Medicine, Eulji University School of Medicine, Seoul, Korea.
Sang Hoon
SH
Kim
Department of Internal Medicine, Inje University College of Medicine, Goyang, Korea.
Jae Won
JW
Jeong
Department of Internal Medicine, Inha University College of Medicine, Incheon, Korea.
Cheol Woo
CW
Kim
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Sang Heon
SH
Cho
Division of Allergy, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. leebj@skku.edu.
Byung Jae
BJ
Lee
Cough; chronic disease; quality of life; questionnaires