Development of a Method for Converting Visual Analogue Scale (VAS) Scores for Pain and Mobility to EQ-5D Answers

Development of a Method for Converting VAS Scores for Pain and Mobility to EQ-5D Answers

The objective of this study is to investigate how mobility and pain scores, measured on a Visual Analogue Scale (VAS), correspond to patients' EuroQol-5Dimensions-3Levels (EQ-5D-3L) answers on pain and mobility. In addition, the investigators want to evaluate patients' undergoing Coronary Artery Bypass Grafting (CABG) quality of life postoperatively, depending on the vein harvesting method used.

Study Overview

• Status: Completed
• Conditions: Cardiovascular Diseases

Detailed Description

Many health economic researchers prefer that a treatments effect is measured in the quantity and quality of life (Qol) the treatment provides. This enables them to calculate effect in the generic Quality Adjusted Life-Years (QALYs). Patients' Qol can be estimates by having patients' answer the EQ-5D-3L questionnaire. However, when performing a post hoc health economic evaluation, data is often incomplete. Often there is no information available regarding the patients' Qol and some health economic researchers therefore resort to various conversions of other measurements of effect to Qol. Such conversions thereby enable them to calculate effect in QALYs even though they had incomplete information. However, no method has been developed for converting eg. VAS pain scores to Qol and the methods currently used are arbitrary. With this study the investigators wish to develop such a method and in the process evaluate our own arbitrary Qol conversion from a prior study by asking the same type of patients. The study is an observational study with no intervention.

• Study Type: Observational
• Enrollment (Actual): 217

Contacts and Locations

Study Locations

• Denmark
  • Region Nord
    • Aalborg, Region Nord, Denmark, 9100
      • Aalborg Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients undergoing CABG

Description

Inclusion Criteria:

• Elective CABG patients
• Use of a vein segment for conduit during CABG

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Endoscopic Vein Harvest (EVH); A short saphenous vein segment is commonly used as a conduit for coronary artery bypass grafting (CABG), and clinicians must decide whether to obtain it by performing a traditional open vein harvest (OVH) or by performing an endoscopic vein harvest (EVH).
Open Vein Harvest (OVH); A short saphenous vein segment is commonly used as a conduit for coronary artery bypass grafting (CABG), and clinicians must decide whether to obtain it by performing a traditional open vein harvest (OVH) or by performing an endoscopic vein harvest (EVH).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The distribution of answers to EQ-5D-3L sub-questions on a 100mm VAS for each sub-question.	The investigators wish to investigate how patients scoring "no pain or discomfort", "moderate pain or discomfort" and "extreme pain or discomfort" on the EQ-5D questionnaire score their pain on a 100mm VAS of pain. The same is done for the four other sub-questions in the EQ-5D, eg. how do patients score their mobility on a 100mm VAS of mobility if they score "no problems in walking about", "some problems in walking about" or "confined to bed" on the EQ-5D. (see citations for similar study setups)	Approximately five days postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Quality of life (Qol)	The investigators will obtain 3 measurements from each patient and are therefore able to evaluate the change in Qol from baseline to approximately 30 days postoperatively in a group of elective bypass patients. Investigators hereby aim to find the incremental Qol. The patient group will be segmented on whether they underwent endoscopic or open vein harvest during their surgery.	approximately 30 days

Collaborators and Investigators

• Sponsor: Lars Oddershede
• Investigators: Study Director: Jan J Andreasen, MD, PhD, Department of Cardiothoracic Surgery, Center for Cardiovascular Research, Aalborg Hospital, Aarhus University Hospital; Principal Investigator: Lars Oddershede, MMSc, Department of Cardiothoracic Surgery, Center for Cardiovascular Research, Aalborg Hospital, Aarhus University Hospital

Publications and helpful links

General Publications

• Jensen MP, Chen C, Brugger AM. Interpretation of visual analog scale ratings and change scores: a reanalysis of two clinical trials of postoperative pain. J Pain. 2003 Sep;4(7):407-14. doi: 10.1016/s1526-5900(03)00716-8.
• Collins SL, Moore RA, McQuay HJ. The visual analogue pain intensity scale: what is moderate pain in millimetres? Pain. 1997 Aug;72(1-2):95-7. doi: 10.1016/s0304-3959(97)00005-5.

Study record dates

Study Major Dates

• Study Start: August 1, 2011
• Primary Completion (Actual): May 1, 2013
• Study Completion (Actual): May 1, 2013

Study Registration Dates

• First Submitted: August 25, 2011
• First Submitted That Met QC Criteria: August 26, 2011
• First Posted (Estimate): August 29, 2011

Study Record Updates

• Last Update Posted (Estimate): June 5, 2013
• Last Update Submitted That Met QC Criteria: June 4, 2013
• Last Verified: June 1, 2013

More Information

Terms related to this study

• Keywords: Quality of life; CABG; VAS; Coronary Artery Bypass Graft; Visual Analogue Scale; Qol; Qol conversion; post hoc HTA
• Additional Relevant MeSH Terms: Cardiovascular Diseases
• Other Study ID Numbers: Oddershede-1