Journal of Clinical and Diagnostic Research, ISSN - 0973 - 709X

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On Sep 2018




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"Journal of Clinical and Diagnostic Research is at present a well-known Indian originated scientific journal which started with a humble beginning. I have been associated with this journal since many years. I appreciate the Editor, Dr. Hemant Jain, for his constant effort in bringing up this journal to the present status right from the scratch. The journal is multidisciplinary. It encourages in publishing the scientific articles from postgraduates and also the beginners who start their career. At the same time the journal also caters for the high quality articles from specialty and super-specialty researchers. Hence it provides a platform for the scientist and researchers to publish. The other aspect of it is, the readers get the information regarding the most recent developments in science which can be used for teaching, research, treating patients and to some extent take preventive measures against certain diseases. The journal is contributing immensely to the society at national and international level."



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Lucknow
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Calcutta National Medical College & Hospital , Kolkata




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Muzaffarnagar.
On Aug 2018




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Dr. Arundhathi. S
MBBS, MD (Pathology),
Sanjay Gandhi institute of trauma and orthopedics,
Bengaluru.
On Aug 2018




Dr. Mamta Gupta,
"It gives me great pleasure to be associated with JCDR, since last 2-3 years. Since then I have authored, co-authored and reviewed about 25 articles in JCDR. I thank JCDR for giving me an opportunity to improve my own skills as an author and a reviewer.
It 's a multispecialty journal, publishing high quality articles. It gives a platform to the authors to publish their research work which can be available for everyone across the globe to read. The best thing about JCDR is that the full articles of all medical specialties are available as pdf/html for reading free of cost or without institutional subscription, which is not there for other journals. For those who have problem in writing manuscript or do statistical work, JCDR comes for their rescue.
The journal has a monthly publication and the articles are published quite fast. In time compared to other journals. The on-line first publication is also a great advantage and facility to review one's own articles before going to print. The response to any query and permission if required, is quite fast; this is quite commendable. I have a very good experience about seeking quick permission for quoting a photograph (Fig.) from a JCDR article for my chapter authored in an E book. I never thought it would be so easy. No hassles.
Reviewing articles is no less a pain staking process and requires in depth perception, knowledge about the topic for review. It requires time and concentration, yet I enjoy doing it. The JCDR website especially for the reviewers is quite user friendly. My suggestions for improving the journal is, more strict review process, so that only high quality articles are published. I find a a good number of articles in Obst. Gynae, hence, a new journal for this specialty titled JCDR-OG can be started. May be a bimonthly or quarterly publication to begin with. Only selected articles should find a place in it.
An yearly reward for the best article authored can also incentivize the authors. Though the process of finding the best article will be not be very easy. I do not know how reviewing process can be improved. If an article is being reviewed by two reviewers, then opinion of one can be communicated to the other or the final opinion of the editor can be communicated to the reviewer if requested for. This will help one’s reviewing skills.
My best wishes to Dr. Hemant Jain and all the editorial staff of JCDR for their untiring efforts to bring out this journal. I strongly recommend medical fraternity to publish their valuable research work in this esteemed journal, JCDR".



Dr. Mamta Gupta
Consultant
(Ex HOD Obs &Gynae, Hindu Rao Hospital and associated NDMC Medical College, Delhi)
Aug 2018




Dr. Rajendra Kumar Ghritlaharey

"I wish to thank Dr. Hemant Jain, Editor-in-Chief Journal of Clinical and Diagnostic Research (JCDR), for asking me to write up few words.
Writing is the representation of language in a textual medium i e; into the words and sentences on paper. Quality medical manuscript writing in particular, demands not only a high-quality research, but also requires accurate and concise communication of findings and conclusions, with adherence to particular journal guidelines. In medical field whether working in teaching, private, or in corporate institution, everyone wants to excel in his / her own field and get recognised by making manuscripts publication.


Authors are the souls of any journal, and deserve much respect. To publish a journal manuscripts are needed from authors. Authors have a great responsibility for producing facts of their work in terms of number and results truthfully and an individual honesty is expected from authors in this regards. Both ways its true "No authors-No manuscripts-No journals" and "No journals–No manuscripts–No authors". Reviewing a manuscript is also a very responsible and important task of any peer-reviewed journal and to be taken seriously. It needs knowledge on the subject, sincerity, honesty and determination. Although the process of reviewing a manuscript is a time consuming task butit is expected to give one's best remarks within the time frame of the journal.
Salient features of the JCDR: It is a biomedical, multidisciplinary (including all medical and dental specialities), e-journal, with wide scope and extensive author support. At the same time, a free text of manuscript is available in HTML and PDF format. There is fast growing authorship and readership with JCDR as this can be judged by the number of articles published in it i e; in Feb 2007 of its first issue, it contained 5 articles only, and now in its recent volume published in April 2011, it contained 67 manuscripts. This e-journal is fulfilling the commitments and objectives sincerely, (as stated by Editor-in-chief in his preface to first edition) i e; to encourage physicians through the internet, especially from the developing countries who witness a spectrum of disease and acquire a wealth of knowledge to publish their experiences to benefit the medical community in patients care. I also feel that many of us have work of substance, newer ideas, adequate clinical materials but poor in medical writing and hesitation to submit the work and need help. JCDR provides authors help in this regards.
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In the era of fast growing newer technologies, and in computer and internet friendly environment the manuscripts preparation, submission, review, revision, etc and all can be done and checked with a click from all corer of the world, at any time. Of course there is always a scope for improvement in every field and none is perfect. To progress, one needs to identify the areas of one's weakness and to strengthen them.
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Every one of us: authors, reviewers, editors, and publisher are responsible for enhancing the stature of the journal. I wish for a great success for JCDR."



Thanking you
With sincere regards
Dr. Rajendra Kumar Ghritlaharey, M.S., M. Ch., FAIS
Associate Professor,
Department of Paediatric Surgery, Gandhi Medical College & Associated
Kamla Nehru & Hamidia Hospitals Bhopal, Madhya Pradesh 462 001 (India)
E-mail: drrajendrak1@rediffmail.com
On May 11,2011




Dr. Shankar P.R.

"On looking back through my Gmail archives after being requested by the journal to write a short editorial about my experiences of publishing with the Journal of Clinical and Diagnostic Research (JCDR), I came across an e-mail from Dr. Hemant Jain, Editor, in March 2007, which introduced the new electronic journal. The main features of the journal which were outlined in the e-mail were extensive author support, cash rewards, the peer review process, and other salient features of the journal.
Over a span of over four years, we (I and my colleagues) have published around 25 articles in the journal. In this editorial, I plan to briefly discuss my experiences of publishing with JCDR and the strengths of the journal and to finally address the areas for improvement.
My experiences of publishing with JCDR: Overall, my experiences of publishing withJCDR have been positive. The best point about the journal is that it responds to queries from the author. This may seem to be simple and not too much to ask for, but unfortunately, many journals in the subcontinent and from many developing countries do not respond or they respond with a long delay to the queries from the authors 1. The reasons could be many, including lack of optimal secretarial and other support. Another problem with many journals is the slowness of the review process. Editorial processing and peer review can take anywhere between a year to two years with some journals. Also, some journals do not keep the contributors informed about the progress of the review process. Due to the long review process, the articles can lose their relevance and topicality. A major benefit with JCDR is the timeliness and promptness of its response. In Dr Jain's e-mail which was sent to me in 2007, before the introduction of the Pre-publishing system, he had stated that he had received my submission and that he would get back to me within seven days and he did!
Most of the manuscripts are published within 3 to 4 months of their submission if they are found to be suitable after the review process. JCDR is published bimonthly and the accepted articles were usually published in the next issue. Recently, due to the increased volume of the submissions, the review process has become slower and it ?? Section can take from 4 to 6 months for the articles to be reviewed. The journal has an extensive author support system and it has recently introduced a paid expedited review process. The journal also mentions the average time for processing the manuscript under different submission systems - regular submission and expedited review.
Strengths of the journal: The journal has an online first facility in which the accepted manuscripts may be published on the website before being included in a regular issue of the journal. This cuts down the time between their acceptance and the publication. The journal is indexed in many databases, though not in PubMed. The editorial board should now take steps to index the journal in PubMed. The journal has a system of notifying readers through e-mail when a new issue is released. Also, the articles are available in both the HTML and the PDF formats. I especially like the new and colorful page format of the journal. Also, the access statistics of the articles are available. The prepublication and the manuscript tracking system are also helpful for the authors.
Areas for improvement: In certain cases, I felt that the peer review process of the manuscripts was not up to international standards and that it should be strengthened. Also, the number of manuscripts in an issue is high and it may be difficult for readers to go through all of them. The journal can consider tightening of the peer review process and increasing the quality standards for the acceptance of the manuscripts. I faced occasional problems with the online manuscript submission (Pre-publishing) system, which have to be addressed.
Overall, the publishing process with JCDR has been smooth, quick and relatively hassle free and I can recommend other authors to consider the journal as an outlet for their work."



Dr. P. Ravi Shankar
KIST Medical College, P.O. Box 14142, Kathmandu, Nepal.
E-mail: ravi.dr.shankar@gmail.com
On April 2011
Anuradha

Dear team JCDR, I would like to thank you for the very professional and polite service provided by everyone at JCDR. While i have been in the field of writing and editing for sometime, this has been my first attempt in publishing a scientific paper.Thank you for hand-holding me through the process.


Dr. Anuradha
E-mail: anuradha2nittur@gmail.com
On Jan 2020

Important Notice

Original article / research
Year : 2021 | Month : July | Volume : 15 | Issue : 7 | Page : YC04 - YC07 Full Version

Test-retest Reliability and Minimum Detectable Change of 2-Minute Walk Test among Individuals with Knee Osteoarthritis


Published: July 1, 2021 | DOI: https://doi.org/10.7860/JCDR/2021/49079.15142
Shefally ChaudHary , Ammar Suhail

1. Postgraduate Research Scholar, Department of Physiotherapy, Lovely Professional University, Phagwara, Punjab, India. 2. Assistant Professor, Department of Physiotherapy, Lovely Professional University, Phagwara, Punjab, India.

Correspondence Address :
Ammar Suhail,
Assistant Professor, Department of Physiotherapy, Lovely Professional University, Jalandhar-Delhi Grand Trunk Road, Phagwara, Punjab, India.
E-mail: asuhail38@gmail.com

Abstract

Introduction: The 2-Minute Walk Test (2MWT) is a simple, practical, and less time consuming test. Patients do not get fatigued while performing this test as a part of routine physical examination. 2MWT shows an excellent correlation with other walk tests and can be used as an alternative test in patients with multiple co-morbidities. The reliability of a test is a must for its recommendation to be used in clinics as well as research. Measurement properties have been reported in different populations for 2MWT. However, no data exist for 2MWT in patients with Knee Osteoarthritis (KOA).

Aim: To establish the test-retest reliability and Minimal Detectable Change (MDC) scores for the 2MWT in patients with bilateral KOA.

Materials and Methods: A prospective test-retest research study designed to assess the reliability of 2MWT. Eighty-two patients with KOA (27 males and 55 females) were included in the study. Health status was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). The Numeric Pain Rating Scale (NPRS) and WOMAC were assessed on two consecutive days. Participants performed 2MWT on two different occasions with 48 hours difference in between. Both sessions were conducted for 45 minutes each on a 30 meter walking pathway. Data was analysed using Statistical Package for the Social Sciences (SPSS) version 20.0 for Windows (SPSS Inc., Chicago, IL, USA).

Results: 2MWT showed an excellent test-retest reliability. Intraclass Correlation Coefficient (ICC) for 2MWT were 0.98. Test-retest reliability assessed by two trials of 2MWT showed 1st trial mean±SD of 154.33±19.59 m and 2nd trial mean±SD of 156.69±19.68 m. Mean difference±SD between both trials was 2.36±2.74, which was statistically significant (p<0.001). The Standard Error of Measurement (SEM) and Minimal Detectable Change at 95% confidence level (MDC95) for 2MWT were 2.76 and 5.52 meters, respectively.

Conclusion: The study recommends that 2MWT can be used as a test for assessing walking capacity among patients with KOA. A change of more than 5.52 meters can be considered as change-free of error. It can be used as an alternative to 6MWT in patients with KOA who cannot tolerate a higher duration/intensity walk test.

Keywords

Outcome measure, Performance-based measures, Walking capacity

Osteoarthritis (OA) is the most ubiquitous form of arthritis (1),(2). Comparatively, knee is 41% more affected than other joints from OA (3). The prevalence of KOA is reported as 28.7% among the Indian population (1). Hip and KOA are significant contributors to disease burden and increased healthcare costs worldwide (2),(4). KOA is associated with pain and can result in difficulty in daily functional tasks such as stair climbing, walking, getting in and out of a chair (5),(6). Balance and gait impairments are frequent findings in participants with KOA (7),(8),(9).

Gait dysfunctions among KOA patients is associated with an increased risk of disease specific mortality (10). These dysfunctions can be measured using either patient-reported or performance-based outcome measures. Performance-based measures are analyser-observed measures of tasks that are assessed through timing, counting, or distance methods (11),(12). These outcome measures assess what individuals can do instead of what they perceive as they can do (13). These tests assess physical functions such as walking speed and capacity (11).

Walk tests are performance-based measures that measure individuals walking capacity. A range of walk tests are used in KOA individuals to estimate the walking capability, such as the 6MWT, 5 m (16.4 ft), multi-paced test, 13 m (42.7 ft) self-paced test. These tests are usually time-based (6MWT or 2MWT) or distance-based (one-mile walk test) (14). A 6MWT and 2MWT are modifications of the 12MWT. High correlations have been reported for 12MWT, 6MWT, and 2MWT in different populations (14). It is suggestive that some individuals are unable to walk for six minutes because of pain, muscle weakness, and low endurance (15). Therefore, 2MWT can be a better practical and tolerable test for KOA affected individuals.

2MWT test’s measurement properties have been studied in various populations (12),(15),(16),17],(18),(19). To the best of our knowledge, the properties of 2MWT have not been tested in KOA (bilateral) individuals. Therefore, the present study aimed at assessing the test-retest reliability of 2MWT among patients with bilateral KOA. It also aimed to analyse the minimum detectable change of 2MWT.

Material and Methods

The study was a prospective test-retest research designed to assess the reliability of 2MWT. Participants were recruited from the Physiotherapy clinic, Department of Physiotherapy, Uni Hospital, Lovely Professional University and Vishwakarma Hospital, Phagwara, Punjab, India. The study was conducted from January 2017 to April 2017. The study was approved by the project approval committee of Lovely Professional University.

Sample size calculation: Sample size was estimated using G power version 3.1. The minimum sample size of included individuals to justify enough power was set at 80. A power analysis determined that a minimum of 78 participants were required to establish a minimally acceptable reliability coefficient of 0.85 with α=0.05.

Inclusion criteria: Eighty-two participants were recruited using purposive sampling in the study. They were included in the study if they: (1) were aged between 45 years or above; (2) had a diagnosis of bilateral KOA (Kellgren-Lawrence (KL) rating >1); (3) had knee pain of ≥3 months; (4) NPRS score ≥3; (5) was able to walk with or without an assistive device.

Exclusion criteria: Participants were excluded if they had a history of a major surgical operation of the lower limb, any previous history of traumatic injury of lower limbs, and surgical history of the spine. Patients who were diagnosed with heart and lung diseases were also excluded from the study.

Procedure

The baseline assessment was done on the first day of the participant’s visit. Health status was assessed using WOMAC (20), (21). The NPRS and WOMAC were assessed on two consecutive days. On the first visit, their necessary information along with pain and health status were assessed. A familiarisation session of 2MWT was conducted before the initial testing. There were two trials of 2MWT to assess the test-retest reliability, with 48 hours interval. The trial sessions lasted for approximately 45 minutes. First author did all the data collection procedures. During the testing procedure, an assistant was present to prevent participants from falling. The scores obtained in the 2MWT were used to ascertain test-retest reliability and MDC. A 2MWT was performed as described by Pin TW (14).

The walk test was performed on a 30 meter walking pathway. The turnaround points were marked with a cone. Participants were instructed to walk at a normal pace and not to run or jog. If the participants felt it necessary to stop at any point in time, they could stop and resume back walking when they felt comfortable. When the time was up, the subject was asked to stop, and the total distance was recorded.

Statistical Analysis

Data was analysed using SPSS 20.0 for Windows (SPSS Inc., Chicago, IL, USA). Shapiro-Wilk test was used to test the normality of the data. The p-values of 0.05 or less were considered significant. The calculation of test-retest reliability for 2MWT was done using the ICC, and the SEM with a 95% confidence interval was determined to confirm the accurateness of the measurement method. The following formulae were used to calculate the SEM and MDC95.

SEM=SD baseline×v1-ICC

MDC 95%=1.96×v2×SEM

Results

The demographic characteristics of the sample are highlighted in (Table/Fig 1). The mean (SD) age of the participants was 60.42 (6.6). Twenty-seven participants were male, and 55 were females. The participant’s NPRS and functional status are shown in (Table/Fig 2), comparing both measurements. The correlation between Body Mass Index (BMI) and 2MWT (Table/Fig 3) (r=0.017), to see if the BMI affected the distance walked, was not significant with a p-value of 0.87.

Reliability of Measure

The test-retest reliability of 2MWT was measured using ICC (2,1). The ICC, MDC, and SEM are presented in (Table/Fig 4). There was a statistical difference between the first and second trial of 2MWT, participants walked 2.36 meters (m) longer in the second trial of 2MWT (p<0.001). The 2MWT showed excellent reliability, ICC was 0.98 (Table/Fig 5).

Limits of Agreement (LOA) Plots

The Bland Altman plot (Table/Fig 4) showed a high level of agreement between the two measurements. There were only five data points outside the +1.96 SD. The mean difference between the measurements was 2.4.

Discussion

The 2MWT showed excellent test-retest reliability in individuals with bilateral KOA. Individuals walked more during the 2nd trial though there was no change in pain or WOMAC score between the two trials. This might be due to learning effect as individuals learned how to do the test.

Reliability of an outcome measure is critical as the information provided should be consistent and responsive to changes in a patient’s condition. Reliability is reflected in terms of consistency and repeatability when administered properly under similar circumstances (22). Clinically, reliability is an essential construct as it helps clinicians correctly interpret the results of a test. In the present study, the test-retest reliability of 2MWT was assessed using the ICC. Test-retest reliability measures test consistency; if the same test is given to the same individuals at different times, it should provide identical scores.

Different studies have evaluated the reliability of 2MWT in different disease populations (12),(17),(18),(19),(22),(23),(24),(25),(26),(27),(28),(29). However, no study has reported test-retest reliability of 2MWT in KOA patients. An excellent test-retest reliability with an ICC of 0.98 (0.9924 to 0.9968) was observed. The ICC used in the study was a two-way random effect, absolute agreement, single rater/measurement usually represented as ICC (2,1) (30). The ICC values' interpretation must depend on the type of ICC used and the measured confidence intervals. A ≥0.9 (ICC) indicates excellent test-retest reliability (30).

In literature, for the 2MWT, ICCs between 0.83 to 0.99 have been reported in distinct populations (12),(16),(25),(26). The present study results agree with the previous studies evaluating test-retest reliability of 2MWT among a diverse population. Resnik L and Borgia M, evaluated test-retest reliability among participants with lower-limb amputations, and they reported an ICC of 0.83 (95% CI) (25). Leung ASY et al., witnessed comparable ICC values of >0.99 were reported in Chronic Obstructive Pulmonary Disease (COPD) Participants (26). Yuksel E et al., reported ICC values of 0.96 and 0.97 among total knee replacement and hip replacement patients respectively. In this study, the value of ICC among bilateral KOA is in accordance with the reported values by Yuksel E et al., (12),(16).

The ICC values must be used along with the SEM and MDC as it alone is of little clinical importance. The values obtained from tests should be useful for clinicians; hence SEM and MDC must also be calculated for any tests to be of value in practice (16). MDC is the bare minimum change in the scores of a tool that must occur in an individual to ensure that the change in score is not merely attributable to measurement error (31). MDC is a statistical concept and is measured using SEM values. MDC calculation requires that participants be measured at two points with minimal difference in between those measurements. Present study measured 2MWT on two different occasions with 48 hours in between the measurements.

In literature, the MDC95 values for 2MWT range from 12.2 m to 34.3 m (14). The highest MDC95 value has been reported as 34.3 m in patients with lower extremity amputation by Resnik L et al., (25). The lowest value was reported as 12.2 m for older adults (29). In the present study, MDC95 for 2MWT was 5.52 m. Compared to other studies, the low MDC95 value is due to specificity associated with the present study population; performance-based measure results are dependent on the population studied. The data showed that individuals walked more on the second day (p<0.001). This could be due to familiarisation with the test as there was no difference in pain score during the study duration.

Limitation(s)

The limitation of the study is that only one aspect of reliability was assessed due to the participants’ availability. The population included in the study was only from two outpatient clinics, thus limiting the generalisability of the findings. The strength of the study is using a standardised protocol of 2MWT. In the literature, different methods of performing the test were described; we used the recommended description of performing the 2MWT as described by Pin TW (14).

Conclusion

The study concluded that 2MWT is a safe and easy test for measuring walking ability among patients with KOA. 2MWT has excellent test-retest reliability for individuals with bilateral KOA. More than 5.52 m changes can be confidently considered actual difference in the patient’s ability to perform the task. Therefore, it is concluded that for functional evaluation in KOA, 2MWT is an excellent alternative to other walk tests such as 6MWT and 12MWT.

Acknowledgement

Authors like to thank Sarah Quais (PT), Consultant Physiotherapist, New Hope Physiocare Physiotherapy Clinic, New Delhi for proofreading the manuscript and helping in the final draft of the manuscript.

References

1.
Pal CP, Singh P, Chaturvedi S, Pruthi KK, Vij A. Epidemiology of knee osteoarthritis in India and related factors. Indian J Orthop. 2016;50:518-22. https://doi.org/10.4103/0019-5413.189608. [crossref] [PubMed]
2.
Safiri S, Kolahi AA, Smith E, Hill C, Bettampadi D, Mansournia MA, et al. Global, regional and national burden of osteoarthritis 1990-2017: A systematic analysis of the global burden of disease study 2017. Annals of the Rheumatic Diseases. 2020;79(6):819-28. [crossref] [PubMed]
3.
Wood AM, Brock TM, Heil K, Holmes R, Weusten A. A review on the management of hip and knee osteoarthritis. Int J Chronic Dis. 2013;2013:845015. [crossref] [PubMed]
4.
Cross M, Smith E, Hoy D, Nolte S, Ackerman I, Fransen M, et al. The global burden of hip and knee osteoarthritis: Estimates from the Global Burden of Disease 2010 study. Ann Rheum Dis. 2014;73(7):1323-30. [crossref] [PubMed]
5.
Foo CN, Manohar A, Rampal L, Lye MS, Mohd-Sidik S, Osman ZJ. Knee pain and functional disability of knee osteoarthritis patients seen at Malaysian government hospitals. Malaysian J Med Heal Sci. 2017;13(2):07-15.
6.
Guccione AA, Felson DT, Anderson JJ, Anthony JM, Zhang Y, Wilson PW, et al. The effects of specific medical conditions on the functional limitations of elders in the Framingham Study. Am J Public Health. 1994;84(3):351-58. https://doi.org/10.2105/AJPH.84.3.351. [crossref] [PubMed]
7.
Kaufman KR, Hughes C, Morrey BF, Morrey M, An KN. Gait characteristics of patients with knee osteoarthritis. J Biomech. 2001;34(7):907-15. https://doi.org/10.1016/S0021-9290(01)00036-7. [crossref]
8.
Farrokhi S, O’Connell M, Fitzgerald GK. Altered gait biomechanics and increased knee-specific impairments in patients with coexisting tibiofemoral and patellofemoral osteoarthritis. Gait Posture. 2015;41(1):81-85. https://doi.org/10.1016/j.gaitpost.2014.08.014. [crossref] [PubMed]
9.
Zeni JA, Higginson JS. Differences in gait parameters between healthy subjects and persons with moderate and severe knee osteoarthritis: A result of altered walking speed? Clin Biomech. 2009;24(4):372-78. https://doi.org/10.1016/j.clinbiomech.2009.02.001. [crossref] [PubMed]
10.
Nüesch E, Dieppe P, Reichenbach S, Williams S, Iff S, Jüni P. All cause and disease specific mortality in patients with knee or hip osteoarthritis: Population based cohort study. BMJ 2011;342:638. https://doi.org/10.1136/bmj.d1165. [crossref] [PubMed]
11.
Terwee CB, Mokkink LB, Steultjens MPM, Dekker J. Performance-based methods for measuring the physical function of patients with osteoarthritis of the hip or knee: A systematic review of measurement properties. Rheumatology. 2006;45(7):890-902. https://doi.org/10.1093/rheumatology/kei267. [crossref] [PubMed]
12.
Yuksel E, Kalkan S, Cekmece S, Unver B, Karatosun V. Assessing minimal detectable changes and test-retest reliability of the timed up and go test and the Two-minute walk test in patients with total knee arthroplasty. J Arthroplasty. 2017;32(2):426-30. https://doi.org/10.1016/j.arth.2016.07.031. [crossref] [PubMed]
13.
Dobson F, Hinman RS, Roos EM, Abbott JH, Stratford P, Davis AM, et al. OARSI recommended performance-based tests to assess physical function in people diagnosed with hip or knee osteoarthritis. Osteoarthr Cartil. 2013;21(8):1042-52. https://doi.org/10.1016/j.joca.2013.05.002. [crossref] [PubMed]
14.
Pin TW. Psychometric properties of 2-minute walk test: A systematic review. Arch Phys Med Rehabil. 2014;95(9):1759-75. https://doi.org/10.1016/j.apmr.2014.03.034. [crossref] [PubMed]
15.
Brooks D, Davis AM, Naglie G. The feasibility of six-minute and two-minute walk tests in in-patient geriatric rehabilitation. Can J Aging/La Rev Can Du Vieil. 2007;26(2):159-62. https://doi.org/10.3138/cja.26.2.009. [crossref] [PubMed]
16.
Yuksel E, Unver B, Kalkan S, Karatosun V. Reliability and minimal detectable change of the 2-minute walk test and Timed Up and Go test in patients with total hip arthroplasty. HIP Int 2021;31(1):43-49. https://doi.org/10.1177/1120700019888614. [crossref] [PubMed]
17.
Brooks D, Parsons J, Tran D, Jeng B, Gorczyca B, Newton J, et al. The two-minute walk test as a measure of functional capacity in cardiac surgery patients. Arch Phys Med Rehabil. 2004;85(9):1525-30. https://doi.org/10.1016/j.apmr.2004.01.023. [crossref] [PubMed]
18.
Eiser N, Willsher D, Doré CJ. Reliability, repeatability and sensitivity to change of externally and self-paced walking tests in COPD patients. Respir Med. 2003;97(4):407-14. https://doi.org/10.1053/rmed.2002.1462. [crossref] [PubMed]
19.
Hiengkaew V, Jitaree K, Chaiyawat P. Minimal detectable changes of the berg balance scale, fugl-meyer assessment scale, timed "up & go" test, gait speeds, and 2-minute walk test in individuals with chronic stroke with different degrees of ankle plantarflexor tone. Arch Phys Med Rehabil. 2012;93(7):1201-08. https://doi.org/10.1016/j.apmr.2012.01.014. [crossref] [PubMed]
20.
Bellamy N, Buchanan WW, Goldsmith CH, Campbell J, Stitt LW. Validation study of WOMAC: A health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee. J Rheumatol. 1988.
21.
McConnell S, Kolopack P, Davis AM. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC): A review of its utility and measurement properties. Arthritis Care Res. 2001;45(5):453-61. https://doi.org/10.1002/1529-0131(200110)45:5<453::aid-art365>3.0.co;2-w. 3.0.CO;2-W>[crossref]
22.
Brooks D, Hunter JP, Parsons J, Livsey E, Quirt J, Devlin M. Reliability of the two-minute walk test in individuals with transtibial amputation. Arch Phys Med Rehabil. 2002;83(11):1562-65. https://doi.org/10.1053/apmr.2002.34600. [crossref] [PubMed]
23.
Brooks D, Parsons J, Hunter JP, Devlin M, Walker J. The 2-minute walk test as a measure of functional improvement in persons with lower limb amputation. Arch Phys Med Rehabil 2001;82(10):1478-83. https://doi.org/10.1053/apmr.2001.25153. [crossref] [PubMed]
24.
Rossier P, Wade DT. Validity and reliability comparison of 4 mobility measures in patients presenting with neurologic impairment. Arch Phys Med Rehabil. 2001;82(1):09-13. https://doi.org/10.1053/apmr.2001.9396. [crossref] [PubMed]
25.
Resnik L, Borgia M. Reliability of outcome measures for people with lower-limb amputations: Distinguishing true change from statistical error. Phys Ther. 2011;91(4):555-65. https://doi.org/10.2522/ptj.20100287. [crossref] [PubMed]
26.
Leung ASY, Chan KK, Sykes K, Chan KS. Reliability, validity, and responsiveness of a 2-min walk test to assess exercise capacity of COPD patients. Chest. 2006;130(1):119-25. https://doi.org/10.1378/chest.130.1.119. [crossref] [PubMed]
27.
Horemans HL, Beelen A, Nollet F, Lankhorst GJ. Reproducibility of walking at self-preferred and maximal speed in patients with postpoliomyelitis syndrome. Arch Phys Med Rehabil. 2004;85(12):1929-32. https://doi.org/10.1016/j.apmr. 2004.04.039. [crossref] [PubMed]
28.
Stolwijk-Swüste JM, Beelen A, Lankhorst GJ, Nollet F, Dekker J, van Dijk GM, et al. SF36 physical functioning scale and 2-minute walk test advocated as core qualifiers to evaluate physical functioning in patients with late-onset sequelae of poliomyelitis. J Rehabil Med. 2008;40(5):387-92. https://doi.org/10.2340/16501977-0188. [crossref] [PubMed]
29.
Connelly DM, Thomas BK, Cliffe SJ, Perry WM, Smith RE. Clinical utility of the 2-minute walk test for older adults living in long-term care. Physiotherapy Canada. 2009;61(2):78-87. [crossref] [PubMed]
30.
Koo TK, Li MY. A guideline of selecting and reporting intraclass correlation coefficients for reliability research. J Chiropr Med. 2016;15(2):155-63. https://doi.org/10.1016/j.jcm.2016.02.012. [crossref] [PubMed]
31.
Stokes EK. Rehabilitation Outcome Measures. Elsevier Ltd; 2011. https://doi.org/10.1016/C2009-0-37125-1. [crossref]

DOI and Others

10.7860/JCDR/2021/49079.15142

Date of Submission: Feb 19, 2021
Date of Peer Review: Apr 09, 2021
Date of Acceptance: May 21, 2021
Date of Publishing: Jul 01, 2021

AUTHOR DECLARATION:
• Financial or Other Competing Interests: None
• Was Ethics Committee Approval obtained for this study? Yes
• Was informed consent obtained from the subjects involved in the study? Yes
• For any images presented appropriate consent has been obtained from the subjects. NA

PLAGIARISM CHECKING METHODS:
• Plagiarism X-checker: Feb 20, 2021
• Manual Googling: May 20, 2021
• iThenticate Software: Jun 02, 2021 (17%)

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