Research article

Unbearability of suffering at the end of life: the development of a new measuring device, the SOS-V

Kees DM Ruijs¹ , Bregje D Onwuteaka-Philipsen² , Gerrit van der Wal² and Ad JFM Kerkhof³

¹Primary Care Center De Greev, Utrecht, the Netherlands

²Department of Public and Occupational Health, EMGO Institute for Health and Care Research, Expertise Center for Palliative Care, VU University Medical Center, Amsterdam, the Netherlands

³Department of Clinical Psychology, EMGO + Institute for Health and Care Research, VU University, Amsterdam, the Netherlands

author email corresponding author email

BMC Palliative Care 2009, 8:16doi:10.1186/1472-684X-8-16

Published:	3 November 2009

Abstract

Background

Unbearable suffering is an important issue in end-of-life decisions. However, there has been no systematic, prospective, patient-oriented research which has focused on unbearable suffering, nor is there a suitable measurement instrument. This article describes the methodological development of a quantitative instrument to measure the nature and intensity of unbearable suffering, practical aspects of its use in end-stage cancer patients in general practice, and studies content validity and psychometric properties.

Methods

Recognizing the conceptual difference between unbearability of suffering and extent or intensity of suffering, we developed an instrument. The compilation of aspects considered to be of importance was based on a literature search. Psychometric properties were determined on results of the first interviews with 64 end-stage cancer patients that participated in a longitudinal study in the Netherlands.

Results

The instrument measures five domains: medical signs and symptoms, loss of function, personal aspects, aspects of environment, and nature and prognosis of the disease. Sixty nine aspects were investigated, and an overall score was asked. In 64 end-stage cancer patients the instrument was used in total 153 times with an average interview time varying from 20-40 minutes. Cronbachs alpha's of the subscales were in majority above 0.7. The sum scores of (sub)scales were correlated strongly to overall measures on suffering.

Conclusion

The SOS-V is an instrument for measuring the unbearability of suffering in end-stage cancer patients with good content validity and psychometric properties, which is feasible to be used in practice. This structured instrument makes it possible to identify and study unbearable suffering in a quantitative and patient-oriented way.