eprintid: 147193 rev_number: 51 eprint_status: archive userid: 608 dir: disk0/00/14/71/93 datestamp: 2010-10-28 10:49:13 lastmod: 2021-09-28 22:16:07 status_changed: 2010-10-28 10:49:13 type: article metadata_visibility: show item_issues_count: 0 creators_name: van der Linden, FAH creators_name: Kragt, JJ creators_name: van Bon, M creators_name: Klein, M creators_name: Thompson, AJ creators_name: van der Ploeg, HM creators_name: Polman, CH creators_name: Uitdehaag, BMJ title: Longitudinal proxy measurements in multiple sclerosis: patient-proxy agreement on the impact of MS on daily life over a period of two years ispublished: pub divisions: UCL divisions: B02 divisions: C07 keywords: QUALITY-OF-LIFE, DISABILITY STATUS SCALE, HEALTH-CARE PROVIDERS, SIGNIFICANT OTHERS, DEPRESSION SCALE, HOSPITAL ANXIETY, CHRONIC DISEASE, OUTCOME MEASURE, HIP FRACTURE, RATINGS note: © 2008 van der Linden et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. abstract: Background: The use of self- report measurements in clinical settings is increasing. However, in patients with limitations that interfere with reliable self- assessment such as cognitive impairment or mood disturbances, as may be the case in multiple sclerosis ( MS), data collection might be problematic. In these situations, information obtained from proxy respondents ( e. g. partners) may replace self- ratings. The aim of this study was to examine the value of proxy ratings at separate points in time and to assess patient- proxy agreement on possible changes in disease impact of MS. Methods: Fifty- six MS patients and their partners completed the Multiple Sclerosis Impact Scale ( MSIS- 29) at baseline and follow- up, two years later. Patient- proxy agreement was assessed at both time points by calculating intraclass correlation coefficients ( ICCs), exact and global agreement and the mean directional differences between groups. Agreement of change over time was assessed by calculating ICCs between change scores. In parallel, global ratings of both patients and proxy respondents of the extent to which the patient had improved or deteriorated over the past two years were collected to validate possible changes on the MSIS- 29. Results: At both time points, agreement on the physical scale was higher than agreement on the psychological scale ( ICCs at baseline were 0.81 for the physical scale and 0.72 for the psychological scale; at follow- up, the ICC values were 0.86 and 0.65 respectively). At follow- up, statistically significant mean differences between patients and proxies were noted for the physical scale (- 4.8 +/- 12.7, p = 0.006) and the psychological scale (- 8.9 +/- 18.8, p = 0.001). Agreement between change scores on the MSIS- 29 was fair ( ICC < 0.60). Our analyses suggest that the validity of measuring changes over time might be better for proxy respondents compared to patients. Conclusion: Proxy respondents could act as a reliable source of information in cross- sectional studies. Moreover, results suggested that agreement on change over time might be better for proxy respondents compared to patients. Although this remarkable finding should be interpreted cautiously because of several limitations of the study, it does plead for further investigation of this important topic. date: 2008-02-28 publisher: BIOMED CENTRAL LTD official_url: http://dx.doi.org/10.1186/1471-2377-8-2 vfaculties: VFBRS oa_status: green language: eng primo: open primo_central: open_green article_type_text: Article verified: verified_batch elements_source: Web of Science elements_id: 99769 doi: 10.1186/1471-2377-8-2 language_elements: EN lyricists_name: Thompson, Alan lyricists_id: ATHOM52 full_text_status: public publication: BMC Neurology volume: 8 article_number: 2 issn: 1471-2377 citation: van der Linden, FAH; Kragt, JJ; van Bon, M; Klein, M; Thompson, AJ; van der Ploeg, HM; Polman, CH; van der Linden, FAH; Kragt, JJ; van Bon, M; Klein, M; Thompson, AJ; van der Ploeg, HM; Polman, CH; Uitdehaag, BMJ; - view fewer <#> (2008) Longitudinal proxy measurements in multiple sclerosis: patient-proxy agreement on the impact of MS on daily life over a period of two years. BMC Neurology , 8 , Article 2. 10.1186/1471-2377-8-2 <https://doi.org/10.1186/1471-2377-8-2>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/147193/1/1471-2377-8-2.pdf