Table 1

Findings and appraisals of studies using stress scale

Taylor (1991), USAKwandt (1992), USARazavi et al (1993), BelgiumTsai and Crockett (1993), TaiwanCarson et al (1999), UKLee and Crockett (1994), TaiwanProctor et al (1998), UK
Symbols: •, Seems no problem; T, treatment group; (E), environmental management; P, placebo group; (P), personnel support; C, control group.
Design features
Population102 nurses31 psychiatric nurses72 nurses134 nurses53 mental health nurses57 nurses84 care assistants
Ta35, Tb34, C33Ta11, Tb10, P10T36, C36T ?, P?T27, P26T29, P28T42, C42
Power analysis
Focus of interventionTa: exerciseTa: humourEducation + role-playing (P)Education + relaxation (P)Social support education (P)Cognitive techniques (P)Education + training (E)
Tb: music (P)Tb: relaxation (P)
Duration6 week (360h)1 session (3h)8 weeks (24h)5 weeks (13.5h)5 weeks (10h)2 weeks (12h)6 months regularly
Reliability and validity of scalePrevious R&V data reportedPrevious R&V mentionedPrevious R statedPrevious V data reportedPrevious R&V mentionedPresent R data reportedR&V not mentioned
Modified by authors
Authors’ conclusionEffectiveNot successful but can reduce stressEffectiveEffectiveNo significant advantageEffectiveNot clear (further research needed)
Validity of results
RandomisationStrategy not clearStrategy not clearQuestionableNot reportedN/A
Sample attrition9, characteristics considered11, not considered in analysis4, not considered in analysis3, not considered in analysis11, not considered in analysis3, not considered in analysis14, not considered in analysis
BlindingNot givenResearcher blindNot givenNot givenNot givenNot given
Similarity at startNot consideredStress levels not reportedStress levels not reportedNot clear
Confounding factorsCharacteristics of control not consideredEqual treatment and effects of placebo not consideredEqual treatment aside from intervention not reportedEffects of placebo on stress not consideredEffects of placebo on stress not consideredPlacebo intervention might worsen stressManagerial climate change during the study
Authenticity of differences
Main outcome (scale)Ta=−4.1 Tb=−1.5Ta=128.9 Tb=137.9Not reportedT=−0.7 C=−0.2T=−3.0 P=−11.5T=−8.1 P=−2.0Larger increase in C than T
Statistical testPost hoc χ2ANCOVAFisherANCOVAWald testANOVAMann-Whitney
Ta-Tb: not significantNot significantNot significantSignificantSignificantSignificantNot significant on all subscales
Ta-C Tb-C: significant
Way of comparisonWithin group analysisMeasurement timing not properTotal score not analysed
Clinical significanceNot clearDescribed but not discussedNot reportedNot clearNot clearNot clearNot clear
Conclusion of appraisalsPotentially effectiveEvaluation impossibleEvaluation impossiblePotentially effectiveQuestioned but possibly effectiveEffective but questionableNo evidence of effectiveness but possibly effective