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Paper text:
chronic kidney disease ( ckd ) is a worldwide chronic disease associated with poor patient quality of life and mental health outcomes as well as high cost . as people with ckd age and present different comorbidities ,
pain is defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage .
pain is a frequent complaint of ckd patients undergoing hemodialysis ( hd ) , though it is not a common focus of research regarding this population .
most published data come indirectly from studies focusing on health - related quality of life .
murtagh et al . , in a review of symptoms in ckd , reported a weighted mean pain prevalence of 47% , with a range of 8 to 82% .
pain can arise in ckd from multiple causes , including surgery , and comorbidities such as osteoarthritis , ischemic limb disease and peripheral neuropathy .
it is known that the presence of chronic pain greatly impacts upon quality of life ( qol ) and can play a major role in the co - morbidity of anxiety and depression .
the aim of the present study is to investigate pain self - efficacy , qol as well as their relation in patients undergoing hd treatment .
because of the fact that the pain self - efficacy questionnaire , which will be used in the context of this study , has not been evaluated before in greece , we aim to investigate its psychometric properties as well .
a cohort of around 70 - 80 patients undergoing hd treatment will be recruited from hospitals located within the broader area of peloponnese .
the inclusion criteria are : i ) > 18 years of age ; ii ) ability of communication in greek ; iii ) diagnosed with ckd ; iv ) hd treatment at least for a year ; v ) satisfying level of cooperation and perceived ability ; vi ) no history of primary psychiatric disease that may interfere with conduct of study ; vii ) clinically stable with no evidence of chronic or acute infections , inflammatory disorders , malignancy .
all subjects will be informed of their rights to refuse or discontinue participation in the study according to the ethical standards of the helsinki declaration .
ethical permission for the study will be obtained from the scientific committees of the participating hospitals .
byock and merriman created the missoula - vitas quality of life index ( mvqoli ) .
the mvqoli is an assessment instrument that gathers patient - reported information about qol during advanced illness .
maintaining optimal qol is a core goal of palliative and hospice care , and information gathered via the mvqoli assists health care professionals in identifying and addressing patient concerns that affect qol . the mvqoli has been used in many different healthcare settings including hospice , hospital , home health , long - term care ( including assisted living ) , outpatient palliative care , disease management and pre - hospice programs .
the framework of the mvqoli is based on ira byock s work regarding growth and development at the end of life and the concepts of landmarks and tasks of life closure .
the mvqoli asks patients about 5 dimensions or domains of qol : symptoms , function , interpersonal , well - being and transcendence .
the instrument is specifically designed to assess the patients personal experience in each of these dimensions , hence the mvqoli items are constructed with highly subjective language and no scores appear on the version of the tool seen by patients .
the tool seeks to describe the qualitative and subjective experience of qol in a way that can be quickly interpreted by professional caregivers .
the pain self - efficacy questionnaire ( pseq ) is a 10-item questionnaire developed to assess the confidence people with ongoing pain have in performing activities while in pain .
it covers a range of functions , including household chores , socializing , work , as well as coping with pain without medication .
demographic and clinical characteristics of all patients will be collected as baseline information at the beginning of the study .
kolmogorov - smirnov tests will be performed in order to check whether the values of the sample fell within a normal distribution . the analyses that will be used in the present study aim to investigate the relation between qol and pain - self efficacy in hd patients .
hierarchical regression analyses will be also used to assess the above association in the total sample .
statistical analyses will be performed with the use of independent samples t test and one - way anova in order to investigate potential effects of socio - demographic factors on qol and pain self - efficacy .
finally , independent samples t test analysis will be used in order to examine differences between patients who recently commenced treatment ( < 4 years ) and those on long term treatment ( > 4 years ) .
all analyses will be performed with the statistical package for the social sciences ( spss 13.0 for windows ) .
two health psychologists will select the data using the relevant psychometric tools in the context of an interview at clinic in order to avoid missing data .
this study will ascertain the association between qol and pain self - efficacy in hd patients .
the findings of the present study can be used in the development of health care services and in - patient management .
the role of qol and pain self - efficacy in particular may play an important role in the course of illness and treatment outcomes and could therefore be identified as a new area for psychological intervention in people with ckd .
patients suffering from end - stage kidney disease often complain about pain . 
 it is also known that the presence of chronic pain greatly impacts upon patients quality of life ( qol ) and can play a crucial role in the co - morbidity of mental health symptoms such as depression and anxiety . 
 the main aim of this study protocol is the investigation of pain self - efficacy , qol as well as their relation in patients undergoing hemodialysis treatment . 
 the final sample size will be around 70 - 80 patients . 
 each subject s qol and pain self - efficacy will be measured using the following instruments : i ) the missoula- itas quality of life index-15 and ii ) the pain self - efficacy questionnaire . 
 qol is expected to be related to pain self - efficacy scores . 
 this probable association will be indicated performing regression as well as correlation analysis after controlling for gender , age , education and marital status .