Christian Kopkow

Prof. Dr. Christian Kopkow

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 February 2020 in BMC Medical Research Methodology
Verified
Journal Article
Open access
PDF file
TLToni Lange
Toni Lange
CKChristian Kopkow
Christian Kopkow
JLJörg Lützner
Jörg Lützner
KGKlaus-Peter Günther
Klaus-Peter Günther
SGSascha Gravius
Sascha Gravius
JSJochen Schmitt
Jochen Schmitt
Background: Consensus-orientated Delphi studies are increasingly used in various areas of medical research using a variety of different rating scales and criteria for reaching consensus. We explored the influence of using three different rating scales and different consensus criteria on the results for reaching consensus and assessed the test-retest reliability of these scales within a study aimed at identification of global treatment goals for total knee arthroplasty (TKA).Methods: We conducted a two-stage study consisting of two surveys and consecutively included patients scheduled for TKA from five German hospitals. Patients were asked to rate 19 potential treatment goals on different rating scales (three-point, five-point, nine-point). Surveys were conducted within a 2 week period prior to TKA, order of questions (scales and treatment goals) was randomized.Results: Eighty patients (mean age 68 ± 10 years; 70% females) completed both surveys. Different rating scales (three-point, five-point and nine-point rating scale) lead to different consensus despite moderate to high correlation between rating scales (r = 0.65 to 0.74). Final consensus was highly influenced by the choice of rating scale with 14 (three-point), 6 (five-point), 15 (nine-point) out of 19 treatment goals reaching the pre-defined 75% consensus threshold. The number of goals reaching consensus also highly varied between rating scales for other consensus thresholds. Overall, concordance differed between the three-point (percent agreement [p] = 88.5%, weighted kappa [k] = 0.63), five-point (p = 75.3%, k = 0.47) and nine-point scale (p = 67.8%, k = 0.78).Conclusion: This study provides evidence that consensus depends on the rating scale and consensus threshold within one population. The test-retest reliability of the three rating scales investigated differs substantially between individual treatment goals. This variation in reliability can become a potential source of bias in consensus studies. In our setting aimed at capturing patients’ treatment goals for TKA, the three-point scale proves to be the most reasonable choice, as its translation into the clinical context is the most straightforward among the scales. Researchers conducting Delphi studies should be aware that final consensus is substantially influenced by the choice of rating scale and consensus criteria.

18 December 2017 in Pain
Verified
Journal Article
Closed access
UKUlrike Kaiser
Ulrike Kaiser
CKChristian Kopkow
Christian Kopkow
SDStefanie Deckert
Stefanie Deckert
KNKatrin Neustadt
Katrin Neustadt
LJLena Jacobi
Lena Jacobi
JSJochen Schmitt
Jochen Schmitt
Interdisciplinary multimodal pain therapy (IMPT) is a biopsychosocial treatment approach for patients with chronic pain that comprises at least psychological and physiotherapeutic interventions. Core outcome sets (COSs) are currently developed in different medical fields to standardize and improve the selection of outcome domains, and measurement instruments in clinical trials, to make trial results meaningful, to pool trial results, and to allow indirect comparison between interventions. The objective of this study was to develop a COS of patient-relevant outcome domains for chronic pain in IMPT clinical trials. An international, multiprofessional panel (patient representatives [n = 5], physicians specialized in pain medicine [n = 5], physiotherapists [n = 5], clinical psychologists [n = 5], and methodological researchers [n = 5]) was recruited for a 3-stage consensus study, which consisted of a mixed-method approach comprising an exploratory systematic review, a preparing online survey to identify important outcome domains, a face-to-face consensus meeting to agree on COS domains, and a second online survey (Delphi) establishing agreement on definitions for the domains included. The panel agreed on the following 8 domains to be included into the COS for IMPT: pain intensity, pain frequency, physical activity, emotional wellbeing, satisfaction with social roles and activities, productivity (paid and unpaid, at home and at work, inclusive presentism and absenteeism), health-related quality of life, and patient's perception of treatment goal achievement. The complexity of chronic pain in a biopsychosocial context is reflected in the current recommendation and includes physical, mental, and social outcomes. In a subsequent step, measurement instruments will be identified via systematic reviews.

21 September 2013 in Allergy
Verified
Journal Article
Closed access
PDF file
SDS. Deckert
S. Deckert
CKChristian Kopkow
Christian Kopkow
JSJ. Schmitt
J. Schmitt

29 May 2015 in European journal of pain
Verified
Journal Article
Closed access
PDF file
SDS. Deckert
S. Deckert
UKU. Kaiser
U. Kaiser
CKChristian Kopkow
Christian Kopkow
FTF. Trautmann
F. Trautmann
RSRainer Sabatowski
Rainer Sabatowski
JSJ. Schmitt
J. Schmitt

1 July 2017 in The Journal of Arthroplasty
Verified
Journal Article
Closed access
TLToni Lange
Toni Lange
JSJochen Schmitt
Jochen Schmitt
CKChristian Kopkow
Christian Kopkow
ERElisabeth Rataj
Elisabeth Rataj
KGKlaus-Peter Günther
Klaus-Peter Günther
JLJörg Lützner
Jörg Lützner

1 November 2013 in Journal of Orthopaedic & Sports Physical Therapy
Verified
Journal Article
Closed access
CKChristian Kopkow
Christian Kopkow
AFAlice Freiberg
Alice Freiberg
SKStephan Kirschner
Stephan Kirschner
ASAndreas Seidler
Andreas Seidler
JSJochen Schmitt
Jochen Schmitt
Study Design: Systematic literature review. Objectives: To summarize and evaluate research on the accuracy of physical examination tests for diagnosis of posterior cruciate ligament (PCL) tear. Background: Rupture of the PCL is a severe knee injury that can lead to delayed rehabilitation, instability, or chronic knee pathologies. To our knowledge, there is currently no systematic review of studies on the diagnostic accuracy of clinical examination tests to evaluate the integrity of the PCL. Methods: A comprehensive systematic literature search was conducted in MEDLINE from 1946, Embase from 1974, and the Allied and Complementary Medicine Database from 1985 until April 30, 2012. Studies were considered eligible if they compared the results of physical examination tests performed in the context of a PCL physical examination to those of a reference standard (arthroscopy, arthrotomy, magnetic resonance imaging). Methodological quality assessment was performed by 2 independent reviewers using the revised version of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Results: The search strategy revealed 1307 articles, of which 11 met the inclusion criteria for this review. In these studies, 11 different physical examination tests were identified. Due to differences in study types, different patient populations, and methodological quality, meta-analysis was not indicated. Presently, most physical examination tests have not been evaluated sufficiently enough to be confident in their ability to either confirm or rule out a PCL tear. Conclusions: The diagnostic accuracy of physical examination tests to assess the integrity of the PCL is largely unknown. There is a strong need for further research in this area. Level of Evidence: Diagnosis, level 3a. J Orthop Sports Phys Ther 2013;43(11):804–813. Epub 10 October 2013. doi:10.2519/jospt.2013.4906