DevelopmentofthePain-RelatedBeliefsandAPtudes
aboutSleep(PBAS)scalefortheassessmentand
treatmentofinsomniacomorbidwithchronicpain
EstherF.Afolalu1,CorranMoore1,FatanahRamlee1,ClaireE.Goodchild2,&NicoleK.Y.Tang1
1DepartmentofPsychology,UniversityofWarwick,UK.2DepartmentofPsychology,InsLtuteofPsychiatry,UK.
INTRODUCTION
Table2SAMPLECHARACTERISTICS
Maladap&ve beliefs about the sleep-pain interac&on are possible
factors underlying perpetua&on of sleep disturbances in chronic
pain-related insomnia. However, there is currently no validated
instrumentthatspecificallyassessesthesebeliefs.
We evaluated the psychometric and func&onal proper&es of a 10item Pain-Related Beliefs and AEtudes about Sleep (PBAS) scale
(Table 1), designed to assess pain-related dysfunc&onal beliefs and
aEtudesaboutsleepamongpeoplewithchronicpain.
METHODS
ThePBASscalewasadministeredtofourclinicalsamplesofchronic
pain pa&ents with comorbid insomnia (Table 2); to examine the
scale’spsychometricproper&es(n=137),test-retestreliability(n=26),
sensi&vity to treatment (n=20), and generalizability in a separate
groupofchronicpainpa&entswithorwithoutinsomnia(n=62).
Par&cipantsalsocompletedtheBriefPainInventory(BPI),Insomnia
Severity Index (ISI), Dysfunc&onal Beliefs and AEtudes about Sleep
Scale (DBAS-16) & Anxiety and Preoccupa&on about Sleep
Ques&onnaire(APSQ).
RESULTS
Table1FACTORSTRUCTURE&INTERNALCONSISTENCY
FACTOR1
FACTOR2
PAIN
NEGATIVE
StronglyDisagreeStronglyAgree
M INTERFERING RECIPROCAL
012345678910
SLEEP
LINKBETWEEN
SLEEPANDPAIN
0.17
Myinsomniaislargelyaresultofthe
6.47
0.79
painandthereisnothingIcandoabout
it.
Withthepain,Icannevergetmyself
comfortableinbed.
Thepainisalwaystherewhenyoutryto
haveagoodnight’ssleep.
WhenIaminpain,Isimplycan’tgetto
sleepnomaXerhowhardItry.
IknowIcan’tsleepthroughthenight
becausethepainwillwakemeup.
7.50
0.82
0.12
7.31
0.78
0.05
6.94
0.64
0.31
6.42
0.64
0.32
Igetveryannoyedwhenthepainwakes
meup.
6.39
0.18
0.64
Notsleepingwellisgoingtomakemy
painworsethenextday.
Iwon’tbeabletocopewiththepainifI
5.01
0.06
0.83
4.68
0.11
0.88
UnlessIgetridofthepain,Iwon’tsleep
well.
5.98
0.26
0.65
Theinsomniaistakingawayoneofmy
fewrespitesfrompain.
5.56
0.24
0.65
58.81
Internalconsistency(α)ofitemsinbold 0.84
29.15
0.82
29.66
0.81
Meanscore(SD)ofitemsinbold
6.93
(2.14)
5.53
(2.51)
don’tsleepwell.
Varianceaccountedfor(R2)
6.23
(2.00)
CONCURRENTVALIDITY
In Sample 1, PBAS scores significantly correlated moderately
withDBAS-16(r=.65),APSQ(r=.57)andISI(r=.37)
Sample 4 PBAS scores also showed significant moderate
correla&onswithDBAS-16(r=.57),APSQ(r=.45)andISI(r=.64)
Age(yrs)
Sex(Female%)
Ethnicity
(Caucasian%)
PainduraLon
(yrs)
Painseverity
(0-10NRS)
InsomniaduraLon
(yrs)
Insomniaseverity
(ISI)
Sample1
(n=137)
Sample2
(n=26)
Sample3
(n=20)
Sample4
(n=62)
46.0(11.3)
75.9
72.3
50.1(10.5)
53.8
80.8
48.5(8.9)
90.0
65.0
52.3(11.1)
67.7
100
8
4.3
6.1
8
5.7(2.6)
6.1(2.3)
6.1(1.8)
5.1(2.3)
5
4
6
4.5
20.4(3.9)
20.4(3.6)
20.3(3.3)
14.4(8.0)
Figure1TEMPORALSTABILITY
SignificantcorrelaLon(r=0.91)&nosignificantchangebetween
PBASmeanscoresoneweekapart(t(25)=0.44,p=0.66)
10
8
6
4
2
0
0
1
2
3
4
5
6
7
8
9
10
Figure2TREATMENTSENSITVITY
Significant reducLons in mean PBAS scores from pre to post-
treatment following hybrid cogniLve behavioural therapy for
sleep&painmanagement(t(19)=6.94,p<0.0001,r=.85)
10
8
6
4
2
0
Pre-Treatment
Post-Treatment
PREDICTIVEVALIDITY
Using a stepwise mul&ple regression model, PBAS scores
significantly predicted ISI scores individually accoun&ng for 14%
and 40% of the variance respec&vely in Sample 1 and Sample 4.
PBAS also jointly predicted ISI scores with DBAS-16 in Sample 1
accoun&ngfor17%ofthevariance&withAPSQscoresinSample
4accoun&ngfor47%ofthevariance.
Only PBAS scores emerged as a significant predictor of BPI pain
interference scores in Sample 1, accoun&ng for 14% of the
variance.
CONCLUSIONS
Pain-relatedsleepbeliefsappeartobeanintegralpartofchronic
painpa&ents’insomniaexperience.
These ini&al findings suggest that the PBAS can be used as a
reliable, valid, and easily administered tool to quan&fy these
perceivedbeliefs.
Contact:e.f.afolalu@warwick.ac.uk