SolutionManual for
Statistics for Nursing
Research A Workbook
for Evidence-Based
Practice 3rd Edition
SusanGrove Daisha
,Answer Guidelines for Questions to Be Graded
EXERCISE
Identifying Levels of
Measurement: Nominal,
Ordinal, Interval, and Ratio
1
The ilquestions ilare ilin ilbold ilfollowed ilby ilanswers.
1. In ilTable il1, ilidentify ilthe illevel ilof ilmeasurement ilfor ilthe ilcurrent iltherapy ilvariable.
ilProvide ila ilrationale ilfor ilyour ilanswer.
Answer: ilThe ilcurrent iltherapy ilvariable ilwas ilmeasured ilat ilthe ilnominal illevel. ilThese ildrug
ilcategories liwere ilprobably ildeveloped ilto ilbe ilexhaustive ilfor ilthis ilstudy iland ilincluded ilthe
ilcategories ilof ildrugs ilthe lisubjects ilwere ilreceiving. ilHowever, ilthe ilcategories ilare ilnot
ilexclusive, ilsince ilpatients ilare ilusually ilon ilmore ilthan ilone ilcategory ilof ilthese ildrugs ilto
ilmanage iltheir ilhealth ilproblems. ilThe ilcurrent iltherapies ilare ilnot ilmeasured ilat ilthe ilordinal
illevel ilbecause ilthey ilcannot ilbe ilrank ilordered, ilsince ilno ildrug ilcategory ilcan ilbe ilconsidered
ilmore ilor illess ilbeneficial ilthan ilanother ildrug ilcategory il(see ilFigure il1-1; ilGrove il& ilGray,
il2019).
2. What i l is i l the i l mode i l for i l the i l current i l therapy i l variable i l in i l this i l study? i l Provide
i l a i l rationale i l forliyour ilanswer.
Answer: il The il mode il for il current il therapy il was il β ilblocker. il A il total il of il 100 il (94%) il of il the
il cardiac il patients
were i l receiving i l this i l category i l of i l drug, i l which i l was i l the i l most i l common
i l prescribed i l drug i l for i l thislisample.
3. What ilstatistics ilwere ilconducted ilto ildescribe ilthe ilBMI ilof ilthe ilcardiac ilpatients ilin
ilthis ilsample? liDiscuss ilwhether ilthese ilanalysis iltechniques ilwere ilappropriate ilor
ilinappropriate.
Answer: il BMI il was il described il with il a il mean il and il standard il deviation il (SD). il BMI
il measurement il resulted ilin ilratio-level ildata ilwith ilcontinuous ilvalues iland ilan ilabsolute ilzero
il(Stone il& ilFrazier, il2017). ilRatio- illevel ildata ilshould ilbe ilanalyzed ilwith ilparametric
ilstatistics ilsuch ilas ilthe ilmean iland ilSD il(Grove il& ilGray,li2017; ilKnapp, il2017).
4. Researchers ilused ilthe ilfollowing ilitem ilto ilmeasure ilregistered ilnurses’ il(RNs) ilincome ilin
ila ilstudy:liWhat ilcategory ilidentifies ilyour ilcurrent ilincome ilas ilan ilRN?
a. i l Less ilthan il$50,000
b. i l $50,000 ilto il59,999
c. i l $60,000 ilto il69,999
d. i l $70,000 ilto il80,000
e. i l $80,000 ilor ilgreater
What il level il of il measurement il is il this il income i l variable? il Does il the il income il variable
il follow il the ilrules iloutlined ilin ilFigure il1-1? ilProvide ila ilrationale ilfor ilyour ilanswer.
Answer: ilIn ilthis ilexample, ilthe ilincome ilvariable ilis ilmeasured ilat ilthe ilordinal illevel. ilThe
il income il catego- ilries ilare ilexhaustive, ilranging ilfrom illess ilthan il$50,000 ilto ilgreater ilthan
il$80,000. ilThe iltwo ilopen-ended
,AG il1-1
, AG il1-2 Answer i l Guidelines i l for i l Questions i l to i l Be i l Graded
categories ilensure ilthat ilall ilsalary illevels ilare ilcovered. ilThe ilcategories ilare ilnot ilexclusive, ilsince
ilcatego- liries il(d) iland il(e) ilinclude ilan il$80,000 ilsalary, ilso ilstudy ilparticipants ilmaking
il$80,000 ilmight ilmark ileither il (d) il or il (e) il or il both il categories, il resulting il in il erroneous
il data. il Category il (e) il could il be il changed lito ilgreater ilthan il$80,000, ilmaking ilthe ilcategories
ilexclusive. ilThe ilcategories ilcan ilbe ilrank ilordered ilfrom ilthe illowest ilsalary ilto ilthe ilhighest
ilsalary, ilwhich ilis ilconsistent ilwith ilordinal ildata il(Grove il& ilGray, il2019; ilWaltz ilet ilal.,
il2017).
5. What illevel ilof ilmeasurement ilis ilthe ilCDS ilscore? ilProvide ila ilrationale ilfor ilyour ilanswer.
Answer: ilThe ilCDS ilscore ilis ilat ilthe ilinterval illevel ilof ilmeasurement. ilThe ilCDS ilis ila il26-
item ilLikert ilscale ildeveloped ilto ilmeasure ildepression ilin ilcardiac ilpatients. ilStudy
ilparticipants ilrated iltheir ilsymp- iltoms ilon ila ilscale ilof il1 ilto il7, ilwith ilhigher ilnumbers
ilindicating ilincreased ilseverity ilin ilthe ildepression ilsymptoms. ilThe iltotal ilscores ilfor ileach
ilsubject ilobtained ilfrom ilthis ilmulti-item ilscale ilare ilconsidered ilto ilbe ilat ilthe ilinterval illevel
ilof ilmeasurement il(Gray ilet ilal., il2017; ilWaltz ilet ilal., il2017).
6. Were ilnonparametric ilor ilparametric ilanalysis iltechniques ilused ilto ilanalyze ilthe ilCDS
ilscores ilforlithe ilcardiac ilpatients ilin ilthis ilstudy? ilProvide ila ilrationale ilfor ilyour ilanswer.
Answer: ilParametric ilstatistics, ilsuch ilas i l mean i l and i l SD, i l were i l conducted i l to
i l describe i l CDS i l scores lifor ilstudy ilparticipants il(see ilTable il1). ilCDS ilscores ilare ilinterval-
level ildata ilas ilindicated ilin ilQuestions il5, ilso ilparametric ilstatistics ilare ilappropriate ilfor ilthis
illevel ilof ildata il(Gray ilet ilal., il2017; ilKim il& ilMallory, il2017).
7. Is ilthe ilprevalence ilof ildepression illinked ilto ilthe ilNYHA ilclass? ilDiscuss ilthe ilclinical
ilimportance ilof ilthis ilresult.
Answer: ilThe ilstudy ilnarrative ilindicated ilthat ilthe ilprevalence ilof ildepression ilincreased
ilwith ilthe ilgreater ilNYHA ilclass. ilIn ilNYHA ilclass ilIII, il64% ilof ilthe ilsubjects ilwere ildepressed,
ilwhereas il11% ilof ilthe lisubjects ilwere ildepressed ilin ilNYHA ilclass ilI. ilThus, ilas ilthe ilNYHA ilclass
ilincreased, ilthe ilnumber ilof ilsub- iljects ilwith ildepression ilincreased. ilThis ilis ilan ilexpected
ilfinding ilbecause ilas ilthe ilNYHA ilclass ilincreases, ilcardiac ilpatients ilhave ilmore ilsevere ilphysical
ilsymptoms, ilwhich ilusually ilresult ilin ilemotional ildistress, ilsuch il as il depression. il Nurses il need
il to il actively il assess il cardiac il patients il for il depression, il especially il those liin ilhigher ilNYHA
ilclasses, ilso ilthey ilmight ilbe ildiagnosed iland iltreated ilas ilneeded.
8. What ilfrequency iland ilpercent ilof ilcardiac ilpatients ilin ilthis ilstudy ilwere ilnot ilbeing
iltreated ilwith ilan ilantidepressant? ilShow ilyour ilcalculations iland ilround ilyour ilanswer
ilto ilthe ilnearest ilwhole ilpercent il(%).
Answer: ilA iltotal il ilof il il106 il ilcardiac il ilpatients il ilparticipated il ilin il ilthis il ilstudy. il ilThe il
ilsample il ilincluded il15 ilpatients ilwho ilwere ilreceiving ilan ilantidepressant il(see ilTable il1).
ilThe il ilnumber il ilof il ilcardiac ilpatients i l not i l treated i l for i l depression i l was i l 91 i l (106 i l –
i l 15 i l = il 91). i l The i l group i l percent i l is i l calculated liby i l the i l following i l formula:
i l (group i l frequency i l ÷ i l total i l sample i l size) i l × i l 100%. i l For i l this i l study, li(91
ilpatients il÷ il106 ilsample ilsize) il× il100% il= il0.858 il× il100% il= il85.8% il= il86%. ilThe il
ilfinal lianswer i l is i l rounded i l to i l the i l nearest i l whole i l percent i l as i l directed i l in i l the
i l question. i l You i l could i l have lialso ilsubtracted ilthe il14% ilof ilpatients iltreated ilwith
ilantidepressants ilfrom il100% iland ilobtained ilthe il86% il who il were il not il treated il with il an
il antidepressant.
9. What ilwas ilthe ilpurpose ilof ilthe il6-minute ilwalk iltest il(6MWT)? ilWould ilthe il6MWT
ilbe iluseful ilin ilclinical ilpractice?
Answer: ilHa ilet ilal. il(2018) ilstated, il―The il6-min ilwalk iltest il(6MWT) ilis ila ilmeasure ilof ilthe
ilsubmaximal, listeady-state ilfunctional ilcapacity‖ ilof ilcardiac ilpatients. ilThis iltest ilwould ilbe ila
ilquick, ileasy ilway ilto ildetermine ila ilcardiac ilpatient’s ilfunctional ilstatus ilin ila ilclinical il
ilsetting. il ilThis il ilfunctional il ilstatus liscore i l could i l be i l used i l to i l determine i l the i l treatment
i l plan i l to i l promote i l or i l maintain i l functional i l statusliof ilcardiac ilpatients.
