title: Reliability, validity and feasibility of quality of life instruments for adult patients with cancer undergoing chemotherapy: result from a systematic review.
abstract: OBJECTIVE
  The aim of this review was to analyse the literature critically and present the best available evidence related to quality of life (QoL) instruments that consists of all four subscales of physical, psychological, social and spiritual, which can be used in the clinical setting to assess adult patients with cancer on chemotherapy.
  
  
  METHODS
  This review included randomised control trials and observational studies without control group related to QoL instruments used for cancer chemotherapy. The types of participants for this review included all adults with cancer over the age of 18 years who have undergone chemotherapy. The QoL instruments for this review included instruments that consist of all subscales of physical, psychological, social and spiritual. In order to retrieve QoL instruments that were current and not outdated, this review included studies reported in the recent 10 years.
  
  
  METHODS
  A three-step search strategy was utilised to search for primary research articles published in the English language from January 1998 to December 2009. An initial search of MEDLINE and CINAHL was undertaken followed by analysis of the text words contained in the title and abstract, and the text terms used to describe the article. A second search strategy using all the identified keywords and the index terms was used for the 20 databases. The third search strategy was to search for additional studies from the relevant list of all identified articles.
  
  
  METHODS
  The two independent reviewers appraised the included articles for methodological quality using the modified Elliot tool for reliability and validity.
  
  
  RESULTS
  A total of 3149 references was retrieved during the initial search. Only 13 articles with validation of the QoL instruments that contained all the four subscales of physical, psychological, social and spiritual were included in this review. Four QoL instruments were identified. These include the City of Hope QOL - Ovarian Cancer Tool (QOL-OVCA), QOL-Breast cancer version (QOL-BC), New India QoL tool and QoL Index-Cancer version (QLI-CV). Among the four identified QoL instruments, the frequency of assessment was more than once for QLI-CV, with intervals of 2 weeks to 6 months. Regarding the number of items, the QOL-BC instrument has the most number of items. All identified QoL instruments have content validity done. For reliability examination, all the identified QoL instruments have Cronbach's alpha of 0.7 and above for subscales. The correlation between subscales scores and overall QoL score was 0.53-0.93, 0.39-0.95 and 0.65-0.83 for QOL-OVCA, QOL-BC and QLI-CV, respectively.
  
  
  CONCLUSIONS
  In this review, there was one article on development of new QoL instrument, the New India QoL tool, which has comprehensive validity examinations - the least number of items that may be useful in the clinical setting but need further psychometric testing in different settings or languages. The QLI-CV instrument has had comprehensive intra- and inter-method validation on different languages, different cultural settings and various types of cancer. However, the instrument may not be feasible because the method to calculate the QoL score is not straightforward.
authors.affiliation: Evidence-Based Nursing Unit, National University Hospital, Singapore. wai_kin_yip@nuhs.edu.sg
authors.forename: Wai Kin
authors.initials: WK
authors.lastname: Yip
authors.forename: Siti Zubaidah
authors.initials: SZ
authors.lastname: Mordiffi
authors.forename: Emily
authors.initials: E
authors.lastname: Ang
mesh_terms: D000328:Adult; D005240:Feasibility Studies; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy / Q000523:psychology*; D011594:Psychometrics; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic; D015203:Reproducibility of Results