Psychometric study of the Persian short-form eight-item Parkinson’s disease questionnaire (PDQ-8) to evaluate health related quality of life (HRQoL)

Health and Quality of Life Outcomes

Johan Lökk²  Ahmad Delbari⁶  Gholam Ali Shahidi⁴  Arash Rahmani⁵  Nader Naderi¹  Seyed-Mohammad Fereshtehnejad³ 

[1] Medical Student Research Committee (MSRC), Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran;Department of Geriatric Medicine, Karolinska University Hospital, Stockholm, Sweden;Karolinska Institutet, Department of Neurobiology, Care Sciences and Society (NVS), Division of Clinical Geriatrics, Novum 5th floor, Stockholm 14186, Sweden;Movement Disorders Clinic, Department of Neurology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran;Mental Health Research Center, Tehran Psychiatry Institute, Iran University of Medical Sciences, Tehran, Iran;Iranian Research Center on Aging, University of Social Welfare and Rehabilitation, Tehran, Iran

关键词: Psychometric properties;    Validity;    Reliability;    Health-related quality of life (HRQoL);    Parkinson’s disease questionnaire (PDQ);    Parkinson’s disease;   

Others  :  814766
DOI  :  10.1186/1477-7525-12-78

 received in 2014-01-08, accepted in 2014-05-15,  发布年份 2014

【 摘 要 】

Background

To assess validation and reliability of the Persian version of the short-form 8-item Parkinson’s disease questionnaire (PDQ-8) and to compare its psychometric properties with that of the long-form questionnaire (PDQ-39) in order to evaluate the health-related quality of life (HRQoL) in patients with Parkinson’s disease (PD).

Methods

This cross-sectional study was conducted on 114 non-demented idiopathic PD (IPD) patients consecutively recruited from an outpatient referral movement disorder clinic. Patients were interviewed to fill in the Persian version of PDQ-39 and PDQ-8 questionnaires and clinical examination was performed to measure disease severity indices.

Results

The Cronbach’s alpha coefficient of the entire PDQ-8 was 0.740 (95% CI: 0.661-0.806). Replacement of PDQ-8 items with other questions with the highest internal consistency within each dimension of the original PDQ-39 did not improve Cronbach’s alpha coefficient [0.723 (95% CI: 0.639-0.794)]. The scores from both PDQ-8 and PDQ-39 had significant correlation with the Hoehn & Yahr (r_PDQ-8 = 0.376, r_PDQ-39 = 0.442), and Schwab & England (r_PDQ-8 = -0.503, r_PDQ-39 = -0.598) disease severity scales and disease duration (r_PDQ-8 = 0.342, r_PDQ-39 = 0.396).

Conclusions

Persian version of the short-form PDQ (PDQ-8) was shown to be a valid and reliable instrument to assess disease-specific HRQoL in a PD population when used independently. Although the PDQ-8 items were not necessarily those with the highest internal consistency in the components of PDQ-39, they entirely showed proper psychometric properties especially in mental and behavioral aspects. PDQ-8 is a practical and informative instrument in daily clinical practice where clinicians are in shortage of time and when a validated self-reported brief questionnaire is of value.

【 授权许可】

   
2014 Fereshtehnejad et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

【 参考文献 】

• [1]Alonso J, Ferrer M, Gandek B, Ware JE Jr, Aaronson NK, Mosconi P, Rasmussen NK, Bullinger M, Fukuhara S, Kaasa S, Leplege A: Health-related quality of life associated with chronic conditions in eight countries: results from the International Quality of Life Assessment (IQOLA) Project. Qual Life Res 2004, 13(2):283-298.
• [2]Chaudhuri KR, Yates L, Martinez-Martin P: The non-motor symptom complex of Parkinson's disease: a comprehensive assessment is essential. Curr Neurol Neurosci Rep 2005, 5(4):275-283.
• [3]Marinus J, Ramaker C, van Hilten JJ, Stiggelbout AM: Health related quality of life in Parkinson's disease: a systematic review of disease specific instruments. J Neurol Neurosurg Psychiatry 2002, 72(2):241-248.
• [4]Cristian A, Katz M, Cutrone E, Walker RH: Evaluation of acupuncture in the treatment of Parkinson's disease: a double-blind pilot study. Mov Disord 2005, 20(9):1185-1188.
• [5]Lyons KE, Pahwa R: Long-term benefits in quality of life provided by bilateral subthalamic stimulation in patients with Parkinson disease. J Neurosurg 2005, 103(2):252-255.
• [6]Rodrigues JP, Edwards DJ, Walters SE, Byrnes ML, Thickbroom G, Stell R, Mastaglia FL: Gabapentin can improve postural stability and quality of life in primary orthostatic tremor. Mov Disord 2005, 20(7):865-870.
• [7]Jenkinson C, Fitzpatrick R: Cross-cultural evaluation of the short form 8-item Parkinson's Disease Questionnaire (PDQ-8): results from America, Canada, Japan, Italy and Spain. Parkinsonism Relat Disord 2007, 13(1):22-28.
• [8]Jenkinson C, Fitzpatrick R, Peto V, Greenhall R, Hyman N: The PDQ-8: development and validation of a shortform Parkinson’s disease questionnaire. Psychol Health 1997, 12:805-814.
• [9]Tan LC, Luo N, Nazri M, Li SC, Thumboo J: Validity and reliability of the PDQ-39 and the PDQ-8 in English-speaking Parkinson's disease patients in Singapore. Parkinsonism Relat Disord 2004, 10(8):493-499.
• [10]Katsarou Z, Bostantjopoulou S, Peto V, Kafantari A, Apostolidou E, Peitsidou E: Assessing quality of life in Parkinson's disease: can a short-form questionnaire be useful? Mov Disord 2004, 19(3):308-312.
• [11]Nojomi M, Mostafavian Z, Shahidi GA, Jenkinson C: Quality of life in patients with Parkinson's disease: translation and psychometric evaluation of the Iranian version of PDQ-39. J Res Med Sci 2010, 15(2):63-69.
• [12]Hughes AJ, Daniel SE, Kilford L, Lees AJ: Accuracy of clinical diagnosis of idiopathic Parkinson's disease: a clinico-pathological study of 100 cases. J Neurol Neurosurg Psychiatry 1992, 55(3):181-184.
• [13]Folstein MF, Folstein SE, McHugh PR: "Mini-mental state". A practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res 1975, 12(3):189-198.
• [14]Movement Disorder Society Task Force on Rating Scales for Parkinson's Disease: The Unified Parkinson's Disease Rating Scale (UPDRS): status and recommendations. Mov Disord 2003, 18(7):738-750.
• [15]Hoehn MM, Yahr MD: Parkinsonism: onset, progression and mortality. Neurology 1967, 17(5):427-442.
• [16]Schwab RS, England AC: Projection techniques for evaluating surgery in Parkinson’s disease. 1969.
• [17]Ramaker C, Marinus J, Stiggelbout AM, Van Hilten BJ: Systematic evaluation of rating scales for impairment and disability in Parkinson's disease. Mov Disord 2002, 17(5):867-876.
• [18]Peto V, Jenkinson C, Fitzpatrick R: PDQ-39: a review of the development, validation and application of a Parkinson's disease quality of life questionnaire and its associated measures. J Neurol 1998, 245(Suppl 1):S10-S14.
• [19]Fayers PM, Machin D: Quality of Life: Assessment, Analysis and Interpretation. New York: John Wiley and Sons; 2000.
• [20]Bandalos DL, Boehm-Kaufman MR: Four common misconceptions in exploratory factor analysis. In Statistical and Methodological Myths and Urban Legends: Doctrine, Verity and Fable in the Organizational and Social Sciences. Edited by Lance CE, Vandenberg RJ. Taylor & Francis; 2008:61-87.
• [21]Carmines EG, Zeller RA: Reliability and validity assessment. C.A: Sage; 1979.
• [22]Cortina J: What is coefficient alpha? An examination of theory and applications. J Appl Psychol 1993, 78(1):98-104.
• [23]Zhang JL, Chan P: Reliability and validity of PDQ-39: a quality-of-life measure for patients with PD in China. Qual Life Res 2012, 21(7):1217-1221.
• [24]Franchignoni F, Giordano A, Ferriero G: Rasch analysis of the short form 8-item Parkinson's Disease Questionnaire (PDQ-8). Qual Life Res 2008, 17(4):541-548.
• [25]Dal Bello-Haas V, Klassen L, Sheppard MS, Metcalfe A: Psychometric properties of activity, self-efficacy, and quality-of-life measures in individuals with Parkinson disease. Physiother Can 2011, 63(1):47-57. doi:10.3138/ptc.2009-3108. Epub 2011 Jan 3120
• [26]Martinez-Martin P, Benito-Leon J, Alonso F, Catalan MJ, Pondal M, Zamarbide I: Health-related quality of life evaluation by proxy in Parkinson's disease: approach using PDQ-8 and EuroQoL-5D. Mov Disord 2004, 19(3):312-318.
• [27]Tan LC, Lau PN, Au WL, Luo N: Validation of PDQ-8 as an independent instrument in English and Chinese. J Neurol Sci 2007, 255(1-2):77-80. Epub 2007 Mar 2002
• [28]Huang TT, Hsu HY, Wang BH, Chen KH: Quality of life in Parkinson's disease patients: validation of the short-form eight-item Parkinson's disease questionnaire (PDQ-8) in Taiwan. Qual Life Res 2011, 20(4):499-505.