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Measuring quality of life in cardiac rehabilitation clients
\ PERGAMON
Int[ J[ Nurs[ Stud[ 24 "0887# 109Ð105
Measuring quality of life in cardiac rehabilitation clients Ellen Rukholm\ Marie McGirr\ Jonathan Potts School of Nursing\ Laurentian University\ Ramsey Lake Road\ Sudbury\ Ontario\ Canada P2E 1C5 Received 2 February 0886^ accepted 18 April 0887
Abstract Quality of life is being increasingly considered as an expected outcome of cardiac rehabilitation programs[ However\ few instruments exist that re~ect a multidimensional concept of quality of life including disease speci_c items[ This article outlines the method used by researchers to adapt Padilla and Grant|s ðPadilla\ G[\ Grant\ M[\ 0874[ Quality of life as a cancer nursing outcome variable[ Adv[ Nursing Sci[ 7"0#\ 34Ð59[Ł Quality of Life Index for use with a cardiac rehabilitation population[ A convenience sample of 111 subjects included three groups] 84 cardiac subjects enrolled in a program^ 40 cardiac subjects not enrolled in a program^ and 65 healthy individuals[ TestÐretest reliability yielded a coe.cient of 9[70 and an alpha coe.cient of 9[76[ Exploratory factor analysis resulted in a _ve factor solution[ These factors explained 59[7) of the variance at loadings of 9[32 or greater[ Contrasted groups approach to validity showed that the instrument di}erentiated between healthy subjects and those with cardiac illness "t 00[46^ df 079^ p³9[9990#[ As anticipated convergent validity revealed a positive correlation between total scores obtained from Spitzer|s ðSpitzer\ W[O[\ Dobson\ A[J[\ Hall\ A[\ Chesterman\ E[\ Levy\ J[\ Shepherd\ R[\ Battista\ R[N[\ Catchlove\ B[R[\ 0870[ Measuring the quality of life in cancer patients] A concise QL index for use by physicians[ J[ Chronic Dis[ 23\ 474Ð486[Ł global measure of quality of life and the Cardiac Quality of Life Index "r 9[56^ p³9[9990#[ This work is preliminary[ Re_nement and development of the instrument is ongoing[ Þ 0887 Elsevier Science Ltd[ All rights reserved[ Keywords] Cardiac^ Quality of life^ Instrument^ Validity^ Reliability[
0[ Introduction The present study grew from research that measured the physical activity level and mood of individuals enrolled in a cardiac rehabilitation program where qual! ity of life was a program goal "McGirr et al[\ 0889#[ Packa "0878# con_rms the importance of measuring quality of life as an outcome of cardiac rehabilitation programs[ The earlier work of McGirr et al[\ 0889 provoked ques! tioning of the completeness of only using the variables of physical activity and mood in assessing quality of life[ Clinical practice suggested that these two variables were too narrow and limited and did not take into account symptoms speci_c to cardiac disease[ A search of the literature revealed that there was a lack of a disease speci_c\ multidimensional instrument to
Corresponding author[ Tel[] ¦0!694!562!5478^ Fax] ¦0! 694!564!3750[
measure quality of life in a cardiac rehabilitation popu! lation[ Packa "0878# emphasized that characteristics of the disease play a role in the meaning of quality of life for the individual[ She argued that characteristics peculiar to cardiac disease and how they a}ect quality of life are di}erent from other diseases[ Symptoms\ characteristic of cardiovascular disease such as heart pain di}er from the nausea and vomiting often associated with cancer[ Measurement of the speci_c symptom characteristic of the disease is important because it has an impact on the individual|s quality of life[ Accordingly\ Packa promoted the inclusion of disease speci_c items in quality of life instruments[ Mayou and Bryant "0882# concurred with Packa|s view[ Furthermore\ Packa suggested there is a need to use a measurement that captures the mul! tidimensional nature of quality of life[ However\ Mayou and Bryant "0882# noted that because of the lack of consensus on the conceptualization of quality of life there is widespread scepticism as to how it can be measured[ With these concerns in mind the current authors adapted a multidimensional\ oncology quality of life instrument
S9919Ð6378:87 ,08[99 Þ 0887 Elsevier Science Ltd[ All rights reserved PII] S 9 9 1 9 Ð 6 3 7 8 " 8 7 # 9 9 9 2 1 Ð 6
E[ Rukholm et al[:Int[ J[ Nurs[ Stud[ 24 "0887# 109Ð105
"Padilla and Grant\ 0874# for a cardiac rehabilitation patient population[ It was anticipated that such an instru! ment could be used as "0# a diagnostic tool for client assessment on admission to a cardiac rehabilitation pro! gram^ "1# a monitoring tool to identify client con! cerns:problems and to therefore assist in planning appro! priate interventions and "2# a long term data collection method for program evaluation and accreditation[ A previous publication "Rukholm and McGirr\ 0883# described the di.culties in conceptualizing and mea! suring quality of life[ The search for a valid and reliable instrument to measure quality of life in a cardiac rehabili! tation population was also outlined[ Finally\ the article related the process of adapting and testing such an instru! ment for this population[ The current article presents the actual reliability and validity _ndings[
1[ Review of the literature 1[0[ De_ning quality of life Although no consensus has been reached on a de_! nition of quality of life many de_nitions revolve around life satisfaction[ Laborde and Powers "0879# have de_ned quality of life within the context of past\ present and future life satisfaction[ In contrast\ Young and Longman "0872# saw it as the degree of satisfaction with perceived present life circumstances[ Olderidge "0875# interpreted quality of life as the sum of satisfactions that make a person|s life worthwhile or as how a person feels and functions in daily life[ Other de_nitions include additional dimensions[ Wenger et al[ "0873# de_ned the concept as three inter! related components consisting of functional capacity\ perceptions and symptoms[ Functional capacity included the ability to perform daily activities as well as social\ intellectual and emotional status[ Perceptions consisted of the individual|s personal view and value judgements of the components of functional capacity[ The last com! ponent related to the symptoms of the speci_c illness[ Burkhardt "0874# considered quality of life as a composite of satisfaction\ physical and mental well!being\ good relations with others\ ability to do extra!curricular activi! ties\ personal development\ ful_llment and recreation[ The Croog et al[ "0875# de_nition was based on _ve measures] a sense of well!being and satisfaction with life\ physical state\ emotional state\ intellectual function and the ability as well as the degree of satisfaction derived from performance in social roles[ The de_nition proposed by Testa et al[ "0882# also noted that quality of life con! sists of _ve components] mental and emotional health\ general health perceptions\ work:daily role well!being\ sexual functioning and physical symptoms[ It is evident from this review that reaching consensus on a de_nition of quality of life is problematic because
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there are so many diverse views[ Furthermore\ it is a complex and multifaceted concept "Packa\ 0878^ Zhan\ 0880#[ However\ Mayou and Bryant "0882# contend that despite these problems the time has come for quality of life assessment to be an expected measurement in car! diovascular rehabilitation[ 1[1[ Quality of life] complex and disease speci_c Faced with this dilemma\ the researchers chose to build on the work of Padilla and Grant "0874# because their de_nition considered both the multifaceted complexity of quality of life as well as disease!speci_c symptoms[ Furthermore\ this instrument had been tested and found to be valid and reliable for use with di}erent patient populations including\ diabetics\ colostomy\ chemo! therapy\ radiation and non!patients[ Padilla et al[ "0872# loosely based their instrument on four general conceptual areas including performance\ personal attitudes and a}ective states\ well!being and support[ Performance refers to the ability to perform normal physical activities\ the ability to work and the ability to engage in normal social activities[ Personal attitudes and a}ective states relates to attitude towards self\ attitude towards one|s life and future and attitude towards treatment[ Well!being addresses health and hos! pitalization\ sleep\ sex\ appetite and symptoms and sup! port refers to familial\ social and:or health care support[ It was noted by Padilla et al[ "0872# that indices of quality of life ~uctuate in importance as changes occur in health status[ Although these researchers described these four general areas they did not clarify the extent to which the original colostomy questionnaire covered the four areas nor did they hypothesize that four factors would emerge from factor analysis[ Padilla and Grant "0874# expanded a 03!item instru! ment developed by Presant et al[ "0870# for palliative care patients by adding 8 items that re~ected the needs of colostomy patients[ This instrument consisted of twenty three visual analogue scales that took into account the four general areas previously described[ Visual analogue scales yield data that are sensitive and have been shown to be a valid and reliable method of measuring a subjective phenomenon "Aitken\ 0858^ Bond and Lader\ 0863^ Revill et al[\ 0865#[ The sources for the items in both studies "Presant et al[\ 0870^ Padilla and Grant\ 0874# were a literature review and the clinical experience of health care professionals[ The study reports did not indi! cate if patients were asked to provide input into item development[ Participants in the current study were also not asked to take part in this process[ 1[2[ A revised instrument] the cardiac quality of life index Revisions and changes were made to the Quality of Life Index developed by Padilla and Grant "0874# to
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E[ Rukholm et al[:Int[ J[ Nurs[ Stud[ 24 "0887# 109Ð105
re~ect the needs of a cardiac rehabilitation population[ The wording in four items was changed and three items were eliminated in an attempt to be cardiac disease spec! i_c[ Item 4\ {worried about your colostomy|\ was changed to {worried about your heart condition|[ Item 7 {ease of adjusting to colostomy| was changed to {ease of adjusting to your heart condition|[ Item 05 {how much pain do you feel| was changed to {how much heart pain do you feel|[ Item 06 {how often do you feel pain| was changed to {how often do you feel heart pain|[ Three items that related speci_cally to colostomy care were removed] item 08\ {fear of odour|^ item 11\ {di.culty of caring for colos! tomy| and item 12\ {is the amount of privacy you have su.cient|[ As a result of revisions the adapted instrument consisted of 19 visual analogues disease speci_c for car! diac clients "Rukholm and McGirr\ 0883#[ This revised instrument was called the Cardiac Quality of Life Index "CQLI#[
2[ Purpose The purpose of this study was to test the adapted CQLI for reliability and validity with a cardiac rehabilitation population[ 2[0[ Method 2[0[0[ Sample[ The convenience sample included a total of 111 subjects] 84 cardiac patients enrolled in a rehabili! tation program\ 40 cardiac patients not enrolled in a rehabilitation program and 65 healthy individuals[ All cardiac patients were automatically referred to the car! diac rehabilitation program on discharge from the hospi! tal[ However\ some patients did not enrol either because they lived too far away\ weren|t interested in a group rehabilitation program\ or didn|t receive information about the program[ These patients were therefore in the non!enrolled group[ Healthy subjects were selected from a variety of work and recreational settings in an attempt to have a comparison group of similar age to the cardiac patient sample[ 2[0[1[ Data collection[ Patients enrolled and those not enrolled in the cardiac rehabilitation program completed the CQLI and a sociodemographic form two weeks post discharge[ This time frame was selected because that is when cardiac rehabilitation patients enter the cardiac program[ The questionnaire was administered by the nurse at the cardiac rehabilitation centre for those sub! jects enrolled in the program[ The non!enrolled subjects were interviewed via telephone after they had been sent the questionnaire in the mail[ Healthy individuals were asked in person to participate in the study[ At that time\ they were invited to complete the questionnaire and then to either immediately return it to the researcher or return
it by mail[ The study received ethical approval from a hospital and a university[ Subjects signed a consent form[ 2[0[2[ Analysis[ All data were analysed using the Stat! istical Package for Social Sciences "SPSS!PC#[ A testÐ retest reliability coe.cient "the Pearson Product Moment Correlation Coe.cient# and an alpha coe.cient were determined "Streiner and Norman\ 0878^ Norman and Streiner\ 0883#[ Content and construct validity were examined[ The contrasted groups approach to construct validity was used to examine the hypothesis that healthy subjects would have a better quality of life than those with cardiovascular disease[ Convergent validity testing was used to see if a known instrument that measured global quality of life "Spitzer et al[\ 0870# correlated with the CQLI[ Factor analysis was used to examine construct validity[ An exploratory approach was taken since we had adapted Padilla and Grant|s instrument by adding items that we thought were relevant based on clinical experience and the cardiac literature[ The purpose was to see if items could be factored into discreet conceptual groupings[
3[ Results Table 0 displays the sociodemographic characteristics of the sample[ There were more males than females in all three groups with the greatest di}erence being in the enrolled cardiac group[ As well\ there were di}erences in age\ education and employment[ For the most part healthy subjects tended to be under 54 years of age\ more highly educated and had a rate of employment almost double that of the cardiac groups[ Total scores were calculated for each of the three groups and these were compared[ The mean total scores\ standard deviations\ ranges and con_dence intervals for the three groups are shown in Table 1 3[0[ Reliability Of the 84 cardiac subjects enrolled in the rehabilitation program\ 65 completed the CQLI on two di}erent occasions\ 6 days apart[ The 6 day time interval was chosen because that was the length of time between pro! gram sessions[ The testÐretest reliability coe.cient was 9[70 "n 65#[ Internal consistency reliability "alpha coe.cient# was 9[76 "n 65#[ Corrected item total cor! relation statistics indicated that there were no odd items that did not appear to _t with the other items[ Item total correlations ranged from 9[19 to 9[69[ According to Streiner and Norman "0878# an item should correlate with the total score above 9[19 and items with lower correlations should be discarded[ They further state that the best coe.cient to use is the Pearson Product Moment Correlation[ Cronbach|s alpha|s were calculated eli!
102
E[ Rukholm et al[:Int[ J[ Nurs[ Stud[ 24 "0887# 109Ð105 Table 0 Demographic characteristics of the sample "N 111# Cardiac subjects enrolled in rehabilitation "N 84#
Cardiac subjects not enrolled in rehabilitation "N 40#
Healthy subjects "N 65#
Age "in years# 21Ð34 35Ð44 45Ð54 ×54 Missing
6 11 24 17 2
2 8 6 8 12
09 27 13 2 0
Gender Male Female Unknown
62 19 1
22 06 0
49 15 9
Education Elementary High school College University Unknown
28 18 03 00 1
12 06 7 1 0
01 14 09 17 0
Native tongue English French Other Unknown
48 13 00 0
20 02 3 2
52 8 3 9
Employment status Employed Not employed
21 51
00 28
44 10
Living arrangement Alone With spouse:partner With relative:friend Other
5 74 1 0
3 33 1 9
1 56 4 1
Table 1 Means\ standard deviations and range of CQLI scores for groups 0\ 1 and 2
Group 0 "cardiac subjects enrolled in the rehabilitation program# Group 1 "healthy subjects# Group 2 "cardiac subjects not enrolled in the rehabilitation program# a b
S[D[ standard deviation[ CI con_dence interval[
Number of subjects
Mean
S[D[a
Range
CIb
84
50[6
09[3
28[74Ð78[77
48[4Ð52[67
65 40
68[7 56[0
8[2 01[3
43[86Ð83[6 25[21Ð81[35
66[63Ð70[87 56[48Ð63[84
103
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minating one item at a time[ There was no signi_cant increase in alpha when each item was left out[ Alpha|s ranged from 9[75 to 9[78[ Therefore no items were discarded[ 3[1[ Content validity Content validity was established by a panel of four cardiovascular nurse experts who reviewed the instru! ment for clarity\ relevance\ comprehensiveness\ under! standability and ease of administration[ No major revisions were required[ 3[2[ Construct validity Construct validity of the contrasted groups type was determined by comparing healthy subjects "n 65# with the combined groups of cardiac subjects "enrolled n 84^ not enrolled n 40#[ The intent here was to compare the group of healthy individuals with the group of all subjects with cardiac illness[ We anticipated that the quality of life of the healthy group would be better than those who were ill[ An unpaired t!test revealed that the 1 groups were di}erent "t 00[46^ df 079^ p³9[9990#[ Convergent validity involved comparisons of CQLI total scores with scores obtained on Spitzer|s 4 item Qual! ity of Life Index "Spitzer et al[\ 0870#[ Spitzer et al[ "0870# developed and tested their global measure of quality of life instrument with Canadian and Australian subjects including healthy individuals and a wide range of chron! ically ill patients[ A high correlation between total scores of the CQLI and Spitzer|s QLI was anticipated since the total scores of each are meant to re~ect overall quality of life[ Positive correlations were achieved between the total mean scores of these two measures "r 9[56^ p ³ 9[9990#[ 3[3[ Factor analysis Factor analysis\ using principal components method with varimax rotation\ resulted in a _ve factor solution on the CQLI "combined cardiac rehabilitation and non! rehabilitation responses "n 039# as determined by eigenvalues greater than one "Kim and Mueller\ 0867^ Ferteich and Muller\ 0889#[ These _ve factors explained 59[7) of the total variance[ Factor loadings on the _ve factors that were 9[32 and greater are included in Table 2[ Factor loadings were determined by the method out! lined by Stevens "0875# and Norman and Streiner "0883#[ An arbitrary cut o} such as 9[2 or 9[3 could be used "Munro and Page\ 0882# however such a method fails to take sample size into account[ Norman and Streiner "0883# suggest that a better way is to retain only those loadings which are statistically signi_cant[ The formula used to calculate the critical value was CV 4[041:−1 yielding a critical value of 9[32[ This formula is based on
the normal curve which is a good approximation for the correlation distribution when N × 099 "Norman and Streiner\ 0883#[ Table 3 includes the CQLI factors\ items in each factor\ alpha coe.cient of each factor and cor! relations between dimensions[ Correlation coe.cients were calculated on combined scores for each factor[
4[ Discussion This study indicated that an adapted instrument administered to a cardiac rehabilitation sample was reliable and that validity results were encouraging for this preliminary stage of instrument testing[ According to Munro and Page "0882# the testÐretest reliability and internal consistency results could be considered strong[ Inter item correlations are high suggesting that none of the items should be eliminated from the instrument and that each is important[ The results of the contrasted groups approach to establishing validity are similar to those of Spitzer et al[ "0870# and Padilla and Grant "0874#[ Both of these researchers reported that healthy subjects had signi_cantly higher quality of life as com! pared to cancer patients[ As anticipated\ healthy subjects in the current study had signi_cantly higher mean CQLI scores than cardiac subjects[ The di}erence between heal! thy individuals and ill cardiac subjects in the current study might be attributed to the inability to control for sociodemographic variables such as\ age\ education and employment[ Convergent validity revealed a positive cor! relation between total scores obtained from Spitzer|s glo! bal measure of quality of life and the CQLI[ Such a correlation suggests that both instruments are likely mea! suring the same construct "Rukholm and McGirr\ 0883#[ Spitzer|s instrument is an overall measure for quality of life in chronically ill subjects[ Similarly\ the CQLI pro! vides an overall measure of quality of life and in addition is also a measure of disease speci_c symptoms and other characteristics clinically known to be peculiar to patients with heart disease[ Therefore a correlation amongst items was expected and found[ The multifaceted and disease speci_c nature of the concept of quality of life as proposed by several researchers "Padilla and Grant\ 0874^ Packa\ 0878^ Mayou and Bryant\ 0882# emerged from the factor analy! sis in the current study as a _ve factor solution[ These _ve factors were loosely related to the four dimensions of the quality of life de_nition\ i[e[ performance\ personal attitudes and a}ective states\ well!being and support[ The investigators named the factors based on common themes suggested by items within each factor[ As in the Padilla and Grant "0874# _ndings\ the most important factor was psychological well!being and included the following items] sexual satisfaction\ adjust! ing to heart condition\ fun\ usefulness\ happiness\ sat! isfaction\ overall quality of life and social contact[ The
104
E[ Rukholm et al[:Int[ J[ Nurs[ Stud[ 24 "0887# 109Ð105 Table 2 Rotated factor loadingsa with orthogonal varimax method for items in the QLI for cardiac patients "N 039# Items
Factor 0
1
Happiness Satisfaction with life Usefulness Fun Overall quality of life Social contact Adjusting to heart condition Sexual satisfaction Tire easily Strength Health Tasks\ usual Heart pain\ intensity Heart pain\ frequency Pleasure in eating Eating enough Weight is a problem Sleep\ su.cient Worry heart condition
9[76 9[74 9[66 9[58 9[58 9[50 9[46 9[42
Percent of explained variance Eigenvalue "principal component method#
16[2 4[3
2
3
4
9[56 9[56 9[51 9[46 9[84 9[84 9[55 9[65 9[70 9[44 9[36 09[5 1[0
7[1 0[5
6[4 0[4
6[1 0[3
a All loadings¾9[32 are omitted[ When items loaded onto two factors the lower loading was omitted[
second factor\ physical well!being\ included] tire easily\ strength\ health and usual tasks[ The third factor\ symp! tom\ was de_ned by two items] heart pain intensity and
heart pain frequency[ The fourth factor was named nutrition and involved the two items of pleasure in eating and eating enough[ Both symptom and nutrition are
Table 3 Cardiac quality of life index factors\ factor items\ correlations\ and alpha coe.cients Factor
Factor 0] psychosocial well being
Psychosocial well being "happiness\ satisfaction with life\ usefulness\ fun\ overall quality of life\ social contact\ adjusting to heart condition\ sexual satisfaction#\ 9[76a Physical well being "tire\ strength\ health\ tasks#\ 9[57a Symptom "heart pain intensity\ heart pain frequency#\ 9[81a Nutrition "pleasure eating\ eating enough#\ 9[53a Worry "weight\ su.cient sleep\ worry heart condition#\ 9[44a
0[99
a
Alpha coe.cients[
Factor 1] Factor 2] physical well being symptom
Factor 3] nutrition
9[3881
0[99
9[9227
9[0654
0[99
9[2504
9[1975
9[9231
0[99
9[1355
9[0655
9[9753
9[9918
Factor 4] worry
0[99
105
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important as disease speci_c factors for this cardiac popu! lation "Rukholm and Bailey\ 0878#[ The _fth factor\ worry\ dealt with items such as weight is a problem\ worry about heart condition and su.cient sleep[ It should be noted that the results of factor analysis are often ambiguous and the eigenvalue criteria for ident! ifying factors is arbitrary at best[ However\ in this study an argument has been made for the usefulness of these factors by linking them to clinical practice observations[ In summary\ this article has presented preliminary work done to establish the validity and reliability of the 19!item CQLI as a multi!faceted\ disease speci_c measure of quality of life in a cardiovascular rehabilitation popu! lation[ The instrument could be used to assess clients on admission to a cardiac rehabilitation program^ to moni! tor and identify their concerns and to evaluate cardiac rehabilitation programs when the twenty items are con! sidered as elements of the quality of life[ The _ndings to date are encouraging and further work on reliability and construct validity to re_ne the instrument continues[ Cur! rently\ the instrument is being used by researchers and practitioners in cardiac rehabilitation centers in Canada\ the USA and Hong Kong[ The work presented here is the beginning of an ongoing process of instrument validation that involves many researchers over a long time[
Acknowledgement This research was supported by a Grant from the Sud! bury Memorial Hospital Foundation and the Canadian Council of Cardiovascular Nurses] a scienti_c Council of the Heart and Stroke Foundation of Canada[ The authors wish to acknowledge the assistance of Dr[ Alnoor Abdulla\ M[D[\ Cardiologist Consultant and Judy Poupore\ Director of the Sudbury Memorial Hospital\ Cardiac Rehabilitation Centre in the conduct of this research[
References Aitken\ R[ 0858[ Measurement of feelings using visual analogue scales[ Proc[ R[ Soc[ Med[ 51\ 878Ð882[ Bond\ A[ and Lader\ M[ 0863[ The use of analogue scales in rating subjective feelings[ Br[ J[ Med[ Psychol[ 36\ 100Ð107[ Burkhardt\ C[S[ 0874[ The impact of arthritis on quality of life[ Nursing Res[ 23"0#\ 00Ð05[ Croog\ S[\ Levine\ S[\ Testa\ M[\ Brown\ B[\ Bulpetl\ C[\ Jenkens\ D[\ Klerman\ G[\ Williams\ G[ 0875[ The e}ects of anti! hypertensive therapy on quality of life[ N[ Engl[ J[ Med[ 203"15#\ 0546Ð0553[ Ferteich\ S[\ Muller\ M[ 0889[ Factor analysis revisited[ Nursing Res[ 28"0#\ 48Ð51[ Kim\ J[O[\ Mueller\ C[W[\ 0867[ Introduction to Factor Analy!
sis] What it is and how to do it[ Series 96!902[ Sage\ Beverly Hills[ Laborde\ J[M[[Powers\ M[J[ 0879[ Satisfaction with life for pat! ients undergoing hemodialysis and patients su}ering from osteoarthritis[ Res[ Nursing Health 2\ 08Ð13[ Mayou\ R[ 0870[ E}ectiveness of cardiac rehabilitation[ J[ Psychosomatic Res[ 14"4#\ 312Ð316[ Mayou\ R[\ Bryant\ B[ 0882[ Quality of life in cardiovascular disease[ Br[ Heart J[ 58\ 359Ð355[ McGirr\ M[\ Rukholm\ E[\ Salmoni\ A[\ O|Sullivan\ P[\ Koren\ I[ 0889[ Perceived mood and exercise behaviours of cardiac rehabilitation program referrals[ Can[ J[ Cardiovasc[ Nursing 0"3#\ 03Ð08[ Munro\ B[\ Page\ E[\ 0882[ Statistical Methods for Health Care Research[ Lippincott\ Philadelphia[ Norman\ G[\ Streiner\ D[\ 0883[ Biostatistics the Bare Essentials[ Mosby\ St[ Louis[ Olderidge\ N[ 0875[ Cardiac rehabilitation\ self!responsibility and quality of life[ J[ Cardiopulmonary Rehab[ 5\ 042Ð045[ Ott\ C[R[\ Sivarajan\ E[S[\ Newton\ K[M[\ Almes\ M[J[\ Bruce\ R[A[\ Bergner\ M[\ Gilson\ B[ S[ 0872[ A controlled ran! domized study of early cardiac rehabilitation] The sickness impact pro_le as an assessment tool[ Heart Lung 01"1#\ 051Ð 069[ Packa\ D[R[ 0878[ Quality of life of cardiac patients] a review[ J[ Cardiovasc[ Nursing 2"1#\ 0Ð00[ Padilla\ G[\ Presant\ C[\ Grant\ M[\ Metter\ G[\ Lipsett\ J[[ Heide\ F[ 0872[ Quality of life index for patients with cancer[ Res[ Nursing Health 5\ 006Ð015[ Padilla\ G[\ Grant\ M[ 0874[ Quality of life as a cancer nursing outcome variable[ Adv[ Nursing Sci[ 7"0#\ 34Ð59[ Presant\ C[\ Klahr\ C[\ Hogan\ L[ 0870[ Evaluating quality of life in oncology patients] Pilot observations[ Oncol[ Nursing Forum 7"2#\ 15Ð29[ Revill\ S[\ Robinson\ J[O[\Rosen\ M[\ Hogg\ M[ 0865[ The reliability of a linear analogue for evaluating pain[ Anaes! thesia 20\ 0080Ð0087[ Rukholm\ E[\ Bailey\ P[ 0878[ Chest pain and the hospitalized cardiac patient[ Can[ J[ Cardiovasc[ Nursing 0"0#\ 04Ð19[ Rukholm\ E[\ McGirr\ M[ 0883[ A quality!of!life index for cli! ents with ischemic heart disease[ Rehab[ Nursing 08"0#\ 01Ð 05[ Spitzer\ W[O[\ Dobson\ A[J[\ Hall\ A[\ Chesterman\ E[\ Levy\ J[\ Shepherd\ R[\ Battista\ R[N[\ Catchlove\ B[R[ 0870[ Mea! suring the quality of life in cancer patients] A concise QL index for use by physicians[ J[ Chronic Dis[ 23\ 474Ð486[ Stevens\ J[\ 0875[ Applied Multivariate Statistics for the Social Sciences[ Lawrence Erlbaum Associates\ Hillsdale\ NJ[ Streiner\ D[\ Norman\ G[\ 0878[ Health Measurement Scales] A Guide to their Practical Development and Use[ Oxford University Press\ New York[ Testa\ M[\ Andrews\ R[\ Nackley\ J[\ Hollenberg\ N[ 0882[ Qual! ity of life and antihypertensive therapy in men] A comparison of Captopril and Enalapril[ N[ Engl[ J[ Med[ 217"02#\ 896Ð 802[ Wenger\ N[\ Mattson\ M[\ Furberg\ C[\ Elinson\ J[ 0873[ Assess! ment of quality of life in clinical trials of cardiovascular ther! apies[ Am[ J[ Cardiol[ 43\ 897Ð802[ Young\ K[J[\ Longman\ A[J[ 0872[ Quality of life and persons with melanoma] A pilot study[ Cancer Nursing 5\ 108Ð114[ Zhan\ L[ 0880[ Quality of life] Conceptual and measurement issues[ J[ Adv[ Nursing 06\ 684Ð799[
Int[ J[ Nurs[ Stud[ 24 "0887# 109Ð105
Measuring quality of life in cardiac rehabilitation clients Ellen Rukholm\ Marie McGirr\ Jonathan Potts School of Nursing\ Laurentian University\ Ramsey Lake Road\ Sudbury\ Ontario\ Canada P2E 1C5 Received 2 February 0886^ accepted 18 April 0887
Abstract Quality of life is being increasingly considered as an expected outcome of cardiac rehabilitation programs[ However\ few instruments exist that re~ect a multidimensional concept of quality of life including disease speci_c items[ This article outlines the method used by researchers to adapt Padilla and Grant|s ðPadilla\ G[\ Grant\ M[\ 0874[ Quality of life as a cancer nursing outcome variable[ Adv[ Nursing Sci[ 7"0#\ 34Ð59[Ł Quality of Life Index for use with a cardiac rehabilitation population[ A convenience sample of 111 subjects included three groups] 84 cardiac subjects enrolled in a program^ 40 cardiac subjects not enrolled in a program^ and 65 healthy individuals[ TestÐretest reliability yielded a coe.cient of 9[70 and an alpha coe.cient of 9[76[ Exploratory factor analysis resulted in a _ve factor solution[ These factors explained 59[7) of the variance at loadings of 9[32 or greater[ Contrasted groups approach to validity showed that the instrument di}erentiated between healthy subjects and those with cardiac illness "t 00[46^ df 079^ p³9[9990#[ As anticipated convergent validity revealed a positive correlation between total scores obtained from Spitzer|s ðSpitzer\ W[O[\ Dobson\ A[J[\ Hall\ A[\ Chesterman\ E[\ Levy\ J[\ Shepherd\ R[\ Battista\ R[N[\ Catchlove\ B[R[\ 0870[ Measuring the quality of life in cancer patients] A concise QL index for use by physicians[ J[ Chronic Dis[ 23\ 474Ð486[Ł global measure of quality of life and the Cardiac Quality of Life Index "r 9[56^ p³9[9990#[ This work is preliminary[ Re_nement and development of the instrument is ongoing[ Þ 0887 Elsevier Science Ltd[ All rights reserved[ Keywords] Cardiac^ Quality of life^ Instrument^ Validity^ Reliability[
0[ Introduction The present study grew from research that measured the physical activity level and mood of individuals enrolled in a cardiac rehabilitation program where qual! ity of life was a program goal "McGirr et al[\ 0889#[ Packa "0878# con_rms the importance of measuring quality of life as an outcome of cardiac rehabilitation programs[ The earlier work of McGirr et al[\ 0889 provoked ques! tioning of the completeness of only using the variables of physical activity and mood in assessing quality of life[ Clinical practice suggested that these two variables were too narrow and limited and did not take into account symptoms speci_c to cardiac disease[ A search of the literature revealed that there was a lack of a disease speci_c\ multidimensional instrument to
Corresponding author[ Tel[] ¦0!694!562!5478^ Fax] ¦0! 694!564!3750[
measure quality of life in a cardiac rehabilitation popu! lation[ Packa "0878# emphasized that characteristics of the disease play a role in the meaning of quality of life for the individual[ She argued that characteristics peculiar to cardiac disease and how they a}ect quality of life are di}erent from other diseases[ Symptoms\ characteristic of cardiovascular disease such as heart pain di}er from the nausea and vomiting often associated with cancer[ Measurement of the speci_c symptom characteristic of the disease is important because it has an impact on the individual|s quality of life[ Accordingly\ Packa promoted the inclusion of disease speci_c items in quality of life instruments[ Mayou and Bryant "0882# concurred with Packa|s view[ Furthermore\ Packa suggested there is a need to use a measurement that captures the mul! tidimensional nature of quality of life[ However\ Mayou and Bryant "0882# noted that because of the lack of consensus on the conceptualization of quality of life there is widespread scepticism as to how it can be measured[ With these concerns in mind the current authors adapted a multidimensional\ oncology quality of life instrument
S9919Ð6378:87 ,08[99 Þ 0887 Elsevier Science Ltd[ All rights reserved PII] S 9 9 1 9 Ð 6 3 7 8 " 8 7 # 9 9 9 2 1 Ð 6
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"Padilla and Grant\ 0874# for a cardiac rehabilitation patient population[ It was anticipated that such an instru! ment could be used as "0# a diagnostic tool for client assessment on admission to a cardiac rehabilitation pro! gram^ "1# a monitoring tool to identify client con! cerns:problems and to therefore assist in planning appro! priate interventions and "2# a long term data collection method for program evaluation and accreditation[ A previous publication "Rukholm and McGirr\ 0883# described the di.culties in conceptualizing and mea! suring quality of life[ The search for a valid and reliable instrument to measure quality of life in a cardiac rehabili! tation population was also outlined[ Finally\ the article related the process of adapting and testing such an instru! ment for this population[ The current article presents the actual reliability and validity _ndings[
1[ Review of the literature 1[0[ De_ning quality of life Although no consensus has been reached on a de_! nition of quality of life many de_nitions revolve around life satisfaction[ Laborde and Powers "0879# have de_ned quality of life within the context of past\ present and future life satisfaction[ In contrast\ Young and Longman "0872# saw it as the degree of satisfaction with perceived present life circumstances[ Olderidge "0875# interpreted quality of life as the sum of satisfactions that make a person|s life worthwhile or as how a person feels and functions in daily life[ Other de_nitions include additional dimensions[ Wenger et al[ "0873# de_ned the concept as three inter! related components consisting of functional capacity\ perceptions and symptoms[ Functional capacity included the ability to perform daily activities as well as social\ intellectual and emotional status[ Perceptions consisted of the individual|s personal view and value judgements of the components of functional capacity[ The last com! ponent related to the symptoms of the speci_c illness[ Burkhardt "0874# considered quality of life as a composite of satisfaction\ physical and mental well!being\ good relations with others\ ability to do extra!curricular activi! ties\ personal development\ ful_llment and recreation[ The Croog et al[ "0875# de_nition was based on _ve measures] a sense of well!being and satisfaction with life\ physical state\ emotional state\ intellectual function and the ability as well as the degree of satisfaction derived from performance in social roles[ The de_nition proposed by Testa et al[ "0882# also noted that quality of life con! sists of _ve components] mental and emotional health\ general health perceptions\ work:daily role well!being\ sexual functioning and physical symptoms[ It is evident from this review that reaching consensus on a de_nition of quality of life is problematic because
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there are so many diverse views[ Furthermore\ it is a complex and multifaceted concept "Packa\ 0878^ Zhan\ 0880#[ However\ Mayou and Bryant "0882# contend that despite these problems the time has come for quality of life assessment to be an expected measurement in car! diovascular rehabilitation[ 1[1[ Quality of life] complex and disease speci_c Faced with this dilemma\ the researchers chose to build on the work of Padilla and Grant "0874# because their de_nition considered both the multifaceted complexity of quality of life as well as disease!speci_c symptoms[ Furthermore\ this instrument had been tested and found to be valid and reliable for use with di}erent patient populations including\ diabetics\ colostomy\ chemo! therapy\ radiation and non!patients[ Padilla et al[ "0872# loosely based their instrument on four general conceptual areas including performance\ personal attitudes and a}ective states\ well!being and support[ Performance refers to the ability to perform normal physical activities\ the ability to work and the ability to engage in normal social activities[ Personal attitudes and a}ective states relates to attitude towards self\ attitude towards one|s life and future and attitude towards treatment[ Well!being addresses health and hos! pitalization\ sleep\ sex\ appetite and symptoms and sup! port refers to familial\ social and:or health care support[ It was noted by Padilla et al[ "0872# that indices of quality of life ~uctuate in importance as changes occur in health status[ Although these researchers described these four general areas they did not clarify the extent to which the original colostomy questionnaire covered the four areas nor did they hypothesize that four factors would emerge from factor analysis[ Padilla and Grant "0874# expanded a 03!item instru! ment developed by Presant et al[ "0870# for palliative care patients by adding 8 items that re~ected the needs of colostomy patients[ This instrument consisted of twenty three visual analogue scales that took into account the four general areas previously described[ Visual analogue scales yield data that are sensitive and have been shown to be a valid and reliable method of measuring a subjective phenomenon "Aitken\ 0858^ Bond and Lader\ 0863^ Revill et al[\ 0865#[ The sources for the items in both studies "Presant et al[\ 0870^ Padilla and Grant\ 0874# were a literature review and the clinical experience of health care professionals[ The study reports did not indi! cate if patients were asked to provide input into item development[ Participants in the current study were also not asked to take part in this process[ 1[2[ A revised instrument] the cardiac quality of life index Revisions and changes were made to the Quality of Life Index developed by Padilla and Grant "0874# to
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re~ect the needs of a cardiac rehabilitation population[ The wording in four items was changed and three items were eliminated in an attempt to be cardiac disease spec! i_c[ Item 4\ {worried about your colostomy|\ was changed to {worried about your heart condition|[ Item 7 {ease of adjusting to colostomy| was changed to {ease of adjusting to your heart condition|[ Item 05 {how much pain do you feel| was changed to {how much heart pain do you feel|[ Item 06 {how often do you feel pain| was changed to {how often do you feel heart pain|[ Three items that related speci_cally to colostomy care were removed] item 08\ {fear of odour|^ item 11\ {di.culty of caring for colos! tomy| and item 12\ {is the amount of privacy you have su.cient|[ As a result of revisions the adapted instrument consisted of 19 visual analogues disease speci_c for car! diac clients "Rukholm and McGirr\ 0883#[ This revised instrument was called the Cardiac Quality of Life Index "CQLI#[
2[ Purpose The purpose of this study was to test the adapted CQLI for reliability and validity with a cardiac rehabilitation population[ 2[0[ Method 2[0[0[ Sample[ The convenience sample included a total of 111 subjects] 84 cardiac patients enrolled in a rehabili! tation program\ 40 cardiac patients not enrolled in a rehabilitation program and 65 healthy individuals[ All cardiac patients were automatically referred to the car! diac rehabilitation program on discharge from the hospi! tal[ However\ some patients did not enrol either because they lived too far away\ weren|t interested in a group rehabilitation program\ or didn|t receive information about the program[ These patients were therefore in the non!enrolled group[ Healthy subjects were selected from a variety of work and recreational settings in an attempt to have a comparison group of similar age to the cardiac patient sample[ 2[0[1[ Data collection[ Patients enrolled and those not enrolled in the cardiac rehabilitation program completed the CQLI and a sociodemographic form two weeks post discharge[ This time frame was selected because that is when cardiac rehabilitation patients enter the cardiac program[ The questionnaire was administered by the nurse at the cardiac rehabilitation centre for those sub! jects enrolled in the program[ The non!enrolled subjects were interviewed via telephone after they had been sent the questionnaire in the mail[ Healthy individuals were asked in person to participate in the study[ At that time\ they were invited to complete the questionnaire and then to either immediately return it to the researcher or return
it by mail[ The study received ethical approval from a hospital and a university[ Subjects signed a consent form[ 2[0[2[ Analysis[ All data were analysed using the Stat! istical Package for Social Sciences "SPSS!PC#[ A testÐ retest reliability coe.cient "the Pearson Product Moment Correlation Coe.cient# and an alpha coe.cient were determined "Streiner and Norman\ 0878^ Norman and Streiner\ 0883#[ Content and construct validity were examined[ The contrasted groups approach to construct validity was used to examine the hypothesis that healthy subjects would have a better quality of life than those with cardiovascular disease[ Convergent validity testing was used to see if a known instrument that measured global quality of life "Spitzer et al[\ 0870# correlated with the CQLI[ Factor analysis was used to examine construct validity[ An exploratory approach was taken since we had adapted Padilla and Grant|s instrument by adding items that we thought were relevant based on clinical experience and the cardiac literature[ The purpose was to see if items could be factored into discreet conceptual groupings[
3[ Results Table 0 displays the sociodemographic characteristics of the sample[ There were more males than females in all three groups with the greatest di}erence being in the enrolled cardiac group[ As well\ there were di}erences in age\ education and employment[ For the most part healthy subjects tended to be under 54 years of age\ more highly educated and had a rate of employment almost double that of the cardiac groups[ Total scores were calculated for each of the three groups and these were compared[ The mean total scores\ standard deviations\ ranges and con_dence intervals for the three groups are shown in Table 1 3[0[ Reliability Of the 84 cardiac subjects enrolled in the rehabilitation program\ 65 completed the CQLI on two di}erent occasions\ 6 days apart[ The 6 day time interval was chosen because that was the length of time between pro! gram sessions[ The testÐretest reliability coe.cient was 9[70 "n 65#[ Internal consistency reliability "alpha coe.cient# was 9[76 "n 65#[ Corrected item total cor! relation statistics indicated that there were no odd items that did not appear to _t with the other items[ Item total correlations ranged from 9[19 to 9[69[ According to Streiner and Norman "0878# an item should correlate with the total score above 9[19 and items with lower correlations should be discarded[ They further state that the best coe.cient to use is the Pearson Product Moment Correlation[ Cronbach|s alpha|s were calculated eli!
102
E[ Rukholm et al[:Int[ J[ Nurs[ Stud[ 24 "0887# 109Ð105 Table 0 Demographic characteristics of the sample "N 111# Cardiac subjects enrolled in rehabilitation "N 84#
Cardiac subjects not enrolled in rehabilitation "N 40#
Healthy subjects "N 65#
Age "in years# 21Ð34 35Ð44 45Ð54 ×54 Missing
6 11 24 17 2
2 8 6 8 12
09 27 13 2 0
Gender Male Female Unknown
62 19 1
22 06 0
49 15 9
Education Elementary High school College University Unknown
28 18 03 00 1
12 06 7 1 0
01 14 09 17 0
Native tongue English French Other Unknown
48 13 00 0
20 02 3 2
52 8 3 9
Employment status Employed Not employed
21 51
00 28
44 10
Living arrangement Alone With spouse:partner With relative:friend Other
5 74 1 0
3 33 1 9
1 56 4 1
Table 1 Means\ standard deviations and range of CQLI scores for groups 0\ 1 and 2
Group 0 "cardiac subjects enrolled in the rehabilitation program# Group 1 "healthy subjects# Group 2 "cardiac subjects not enrolled in the rehabilitation program# a b
S[D[ standard deviation[ CI con_dence interval[
Number of subjects
Mean
S[D[a
Range
CIb
84
50[6
09[3
28[74Ð78[77
48[4Ð52[67
65 40
68[7 56[0
8[2 01[3
43[86Ð83[6 25[21Ð81[35
66[63Ð70[87 56[48Ð63[84
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minating one item at a time[ There was no signi_cant increase in alpha when each item was left out[ Alpha|s ranged from 9[75 to 9[78[ Therefore no items were discarded[ 3[1[ Content validity Content validity was established by a panel of four cardiovascular nurse experts who reviewed the instru! ment for clarity\ relevance\ comprehensiveness\ under! standability and ease of administration[ No major revisions were required[ 3[2[ Construct validity Construct validity of the contrasted groups type was determined by comparing healthy subjects "n 65# with the combined groups of cardiac subjects "enrolled n 84^ not enrolled n 40#[ The intent here was to compare the group of healthy individuals with the group of all subjects with cardiac illness[ We anticipated that the quality of life of the healthy group would be better than those who were ill[ An unpaired t!test revealed that the 1 groups were di}erent "t 00[46^ df 079^ p³9[9990#[ Convergent validity involved comparisons of CQLI total scores with scores obtained on Spitzer|s 4 item Qual! ity of Life Index "Spitzer et al[\ 0870#[ Spitzer et al[ "0870# developed and tested their global measure of quality of life instrument with Canadian and Australian subjects including healthy individuals and a wide range of chron! ically ill patients[ A high correlation between total scores of the CQLI and Spitzer|s QLI was anticipated since the total scores of each are meant to re~ect overall quality of life[ Positive correlations were achieved between the total mean scores of these two measures "r 9[56^ p ³ 9[9990#[ 3[3[ Factor analysis Factor analysis\ using principal components method with varimax rotation\ resulted in a _ve factor solution on the CQLI "combined cardiac rehabilitation and non! rehabilitation responses "n 039# as determined by eigenvalues greater than one "Kim and Mueller\ 0867^ Ferteich and Muller\ 0889#[ These _ve factors explained 59[7) of the total variance[ Factor loadings on the _ve factors that were 9[32 and greater are included in Table 2[ Factor loadings were determined by the method out! lined by Stevens "0875# and Norman and Streiner "0883#[ An arbitrary cut o} such as 9[2 or 9[3 could be used "Munro and Page\ 0882# however such a method fails to take sample size into account[ Norman and Streiner "0883# suggest that a better way is to retain only those loadings which are statistically signi_cant[ The formula used to calculate the critical value was CV 4[041:−1 yielding a critical value of 9[32[ This formula is based on
the normal curve which is a good approximation for the correlation distribution when N × 099 "Norman and Streiner\ 0883#[ Table 3 includes the CQLI factors\ items in each factor\ alpha coe.cient of each factor and cor! relations between dimensions[ Correlation coe.cients were calculated on combined scores for each factor[
4[ Discussion This study indicated that an adapted instrument administered to a cardiac rehabilitation sample was reliable and that validity results were encouraging for this preliminary stage of instrument testing[ According to Munro and Page "0882# the testÐretest reliability and internal consistency results could be considered strong[ Inter item correlations are high suggesting that none of the items should be eliminated from the instrument and that each is important[ The results of the contrasted groups approach to establishing validity are similar to those of Spitzer et al[ "0870# and Padilla and Grant "0874#[ Both of these researchers reported that healthy subjects had signi_cantly higher quality of life as com! pared to cancer patients[ As anticipated\ healthy subjects in the current study had signi_cantly higher mean CQLI scores than cardiac subjects[ The di}erence between heal! thy individuals and ill cardiac subjects in the current study might be attributed to the inability to control for sociodemographic variables such as\ age\ education and employment[ Convergent validity revealed a positive cor! relation between total scores obtained from Spitzer|s glo! bal measure of quality of life and the CQLI[ Such a correlation suggests that both instruments are likely mea! suring the same construct "Rukholm and McGirr\ 0883#[ Spitzer|s instrument is an overall measure for quality of life in chronically ill subjects[ Similarly\ the CQLI pro! vides an overall measure of quality of life and in addition is also a measure of disease speci_c symptoms and other characteristics clinically known to be peculiar to patients with heart disease[ Therefore a correlation amongst items was expected and found[ The multifaceted and disease speci_c nature of the concept of quality of life as proposed by several researchers "Padilla and Grant\ 0874^ Packa\ 0878^ Mayou and Bryant\ 0882# emerged from the factor analy! sis in the current study as a _ve factor solution[ These _ve factors were loosely related to the four dimensions of the quality of life de_nition\ i[e[ performance\ personal attitudes and a}ective states\ well!being and support[ The investigators named the factors based on common themes suggested by items within each factor[ As in the Padilla and Grant "0874# _ndings\ the most important factor was psychological well!being and included the following items] sexual satisfaction\ adjust! ing to heart condition\ fun\ usefulness\ happiness\ sat! isfaction\ overall quality of life and social contact[ The
104
E[ Rukholm et al[:Int[ J[ Nurs[ Stud[ 24 "0887# 109Ð105 Table 2 Rotated factor loadingsa with orthogonal varimax method for items in the QLI for cardiac patients "N 039# Items
Factor 0
1
Happiness Satisfaction with life Usefulness Fun Overall quality of life Social contact Adjusting to heart condition Sexual satisfaction Tire easily Strength Health Tasks\ usual Heart pain\ intensity Heart pain\ frequency Pleasure in eating Eating enough Weight is a problem Sleep\ su.cient Worry heart condition
9[76 9[74 9[66 9[58 9[58 9[50 9[46 9[42
Percent of explained variance Eigenvalue "principal component method#
16[2 4[3
2
3
4
9[56 9[56 9[51 9[46 9[84 9[84 9[55 9[65 9[70 9[44 9[36 09[5 1[0
7[1 0[5
6[4 0[4
6[1 0[3
a All loadings¾9[32 are omitted[ When items loaded onto two factors the lower loading was omitted[
second factor\ physical well!being\ included] tire easily\ strength\ health and usual tasks[ The third factor\ symp! tom\ was de_ned by two items] heart pain intensity and
heart pain frequency[ The fourth factor was named nutrition and involved the two items of pleasure in eating and eating enough[ Both symptom and nutrition are
Table 3 Cardiac quality of life index factors\ factor items\ correlations\ and alpha coe.cients Factor
Factor 0] psychosocial well being
Psychosocial well being "happiness\ satisfaction with life\ usefulness\ fun\ overall quality of life\ social contact\ adjusting to heart condition\ sexual satisfaction#\ 9[76a Physical well being "tire\ strength\ health\ tasks#\ 9[57a Symptom "heart pain intensity\ heart pain frequency#\ 9[81a Nutrition "pleasure eating\ eating enough#\ 9[53a Worry "weight\ su.cient sleep\ worry heart condition#\ 9[44a
0[99
a
Alpha coe.cients[
Factor 1] Factor 2] physical well being symptom
Factor 3] nutrition
9[3881
0[99
9[9227
9[0654
0[99
9[2504
9[1975
9[9231
0[99
9[1355
9[0655
9[9753
9[9918
Factor 4] worry
0[99
105
E[ Rukholm et al[:Int[ J[ Nurs[ Stud[ 24 "0887# 109Ð105
important as disease speci_c factors for this cardiac popu! lation "Rukholm and Bailey\ 0878#[ The _fth factor\ worry\ dealt with items such as weight is a problem\ worry about heart condition and su.cient sleep[ It should be noted that the results of factor analysis are often ambiguous and the eigenvalue criteria for ident! ifying factors is arbitrary at best[ However\ in this study an argument has been made for the usefulness of these factors by linking them to clinical practice observations[ In summary\ this article has presented preliminary work done to establish the validity and reliability of the 19!item CQLI as a multi!faceted\ disease speci_c measure of quality of life in a cardiovascular rehabilitation popu! lation[ The instrument could be used to assess clients on admission to a cardiac rehabilitation program^ to moni! tor and identify their concerns and to evaluate cardiac rehabilitation programs when the twenty items are con! sidered as elements of the quality of life[ The _ndings to date are encouraging and further work on reliability and construct validity to re_ne the instrument continues[ Cur! rently\ the instrument is being used by researchers and practitioners in cardiac rehabilitation centers in Canada\ the USA and Hong Kong[ The work presented here is the beginning of an ongoing process of instrument validation that involves many researchers over a long time[
Acknowledgement This research was supported by a Grant from the Sud! bury Memorial Hospital Foundation and the Canadian Council of Cardiovascular Nurses] a scienti_c Council of the Heart and Stroke Foundation of Canada[ The authors wish to acknowledge the assistance of Dr[ Alnoor Abdulla\ M[D[\ Cardiologist Consultant and Judy Poupore\ Director of the Sudbury Memorial Hospital\ Cardiac Rehabilitation Centre in the conduct of this research[
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sis] What it is and how to do it[ Series 96!902[ Sage\ Beverly Hills[ Laborde\ J[M[[Powers\ M[J[ 0879[ Satisfaction with life for pat! ients undergoing hemodialysis and patients su}ering from osteoarthritis[ Res[ Nursing Health 2\ 08Ð13[ Mayou\ R[ 0870[ E}ectiveness of cardiac rehabilitation[ J[ Psychosomatic Res[ 14"4#\ 312Ð316[ Mayou\ R[\ Bryant\ B[ 0882[ Quality of life in cardiovascular disease[ Br[ Heart J[ 58\ 359Ð355[ McGirr\ M[\ Rukholm\ E[\ Salmoni\ A[\ O|Sullivan\ P[\ Koren\ I[ 0889[ Perceived mood and exercise behaviours of cardiac rehabilitation program referrals[ Can[ J[ Cardiovasc[ Nursing 0"3#\ 03Ð08[ Munro\ B[\ Page\ E[\ 0882[ Statistical Methods for Health Care Research[ Lippincott\ Philadelphia[ Norman\ G[\ Streiner\ D[\ 0883[ Biostatistics the Bare Essentials[ Mosby\ St[ Louis[ Olderidge\ N[ 0875[ Cardiac rehabilitation\ self!responsibility and quality of life[ J[ Cardiopulmonary Rehab[ 5\ 042Ð045[ Ott\ C[R[\ Sivarajan\ E[S[\ Newton\ K[M[\ Almes\ M[J[\ Bruce\ R[A[\ Bergner\ M[\ Gilson\ B[ S[ 0872[ A controlled ran! domized study of early cardiac rehabilitation] The sickness impact pro_le as an assessment tool[ Heart Lung 01"1#\ 051Ð 069[ Packa\ D[R[ 0878[ Quality of life of cardiac patients] a review[ J[ Cardiovasc[ Nursing 2"1#\ 0Ð00[ Padilla\ G[\ Presant\ C[\ Grant\ M[\ Metter\ G[\ Lipsett\ J[[ Heide\ F[ 0872[ Quality of life index for patients with cancer[ Res[ Nursing Health 5\ 006Ð015[ Padilla\ G[\ Grant\ M[ 0874[ Quality of life as a cancer nursing outcome variable[ Adv[ Nursing Sci[ 7"0#\ 34Ð59[ Presant\ C[\ Klahr\ C[\ Hogan\ L[ 0870[ Evaluating quality of life in oncology patients] Pilot observations[ Oncol[ Nursing Forum 7"2#\ 15Ð29[ Revill\ S[\ Robinson\ J[O[\Rosen\ M[\ Hogg\ M[ 0865[ The reliability of a linear analogue for evaluating pain[ Anaes! thesia 20\ 0080Ð0087[ Rukholm\ E[\ Bailey\ P[ 0878[ Chest pain and the hospitalized cardiac patient[ Can[ J[ Cardiovasc[ Nursing 0"0#\ 04Ð19[ Rukholm\ E[\ McGirr\ M[ 0883[ A quality!of!life index for cli! ents with ischemic heart disease[ Rehab[ Nursing 08"0#\ 01Ð 05[ Spitzer\ W[O[\ Dobson\ A[J[\ Hall\ A[\ Chesterman\ E[\ Levy\ J[\ Shepherd\ R[\ Battista\ R[N[\ Catchlove\ B[R[ 0870[ Mea! suring the quality of life in cancer patients] A concise QL index for use by physicians[ J[ Chronic Dis[ 23\ 474Ð486[ Stevens\ J[\ 0875[ Applied Multivariate Statistics for the Social Sciences[ Lawrence Erlbaum Associates\ Hillsdale\ NJ[ Streiner\ D[\ Norman\ G[\ 0878[ Health Measurement Scales] A Guide to their Practical Development and Use[ Oxford University Press\ New York[ Testa\ M[\ Andrews\ R[\ Nackley\ J[\ Hollenberg\ N[ 0882[ Qual! ity of life and antihypertensive therapy in men] A comparison of Captopril and Enalapril[ N[ Engl[ J[ Med[ 217"02#\ 896Ð 802[ Wenger\ N[\ Mattson\ M[\ Furberg\ C[\ Elinson\ J[ 0873[ Assess! ment of quality of life in clinical trials of cardiovascular ther! apies[ Am[ J[ Cardiol[ 43\ 897Ð802[ Young\ K[J[\ Longman\ A[J[ 0872[ Quality of life and persons with melanoma] A pilot study[ Cancer Nursing 5\ 108Ð114[ Zhan\ L[ 0880[ Quality of life] Conceptual and measurement issues[ J[ Adv[ Nursing 06\ 684Ð799[