Beth Pollard

Construct validation of the hospital anxiety and depression scale with clinical populations

OBJECTIVE the hospital anxiety and depression scale (HADS) attempts to measure anxiety and depression without confounding by somatic symptoms of physical disorder, and is widely used for this purpose. This paper addresses three questions about the validity of the HADS concerning its independence of physical symptoms, the extent to which its items robustly measure the identified constructs with varying clinical populations and situations, and its capacity to differentiate anxiety and depression. METHODS data from patients with breast disease, myocardial infarction (MI), and stroke were examined using factor analytic and psychometric analyses. RESULTS using exploratory factor analysis in patients with breast disease, 13 of the 14 HADS items fell on a psychological factor and loadings on the psychological factor were higher than loadings on the somatic factor for all items. The HADS showed high levels of internal consistency and there was little evidence that removing items would improve it. Confirmatory factor analyses (CFA) in MI and stroke groups confirmed the separation of anxiety and depression. Analyses indicated items, which were performing poorly for these clinical groups. CONCLUSIONS there was support for the validity of the HADS for all three questions. However, there were some evidences of individual items performing poorly. Given the ease of administration and the acceptability of this measure to ill or weak respondents, the HADS continues to perform satisfactorily.

Motivation is not enough: Prediction of risk behavior following diagnosis of coronary heart disease from the theory of planned behavior

Perceived behavioral control (PBC) and intention, the proximal predictors from the theory of planned behavior (TPB), were used to predict cardiovascular risk behaviors in 597 patients 1 year after diagnosis with coronary heart disease. The outcome measures were self-report measures of exercise plus objective measures of fitness (distance walked in 6 min) and cotinine-confirmed smoking cessation. In multivariate analyses incorporating both PBC and intention, PBC predicted exercise, distance walked, and smoking cessation, but intention was not a reliable independent predictor of any health behavior measured. Thus, the effective theoretical component of the TPB was PBC. Similar predictions could derive from social-cognitive theory. In coronary patients, behavioral change needs to address issues of action implementation rather than motivational factors alone.

Impact on patients and partners of inpatient and extended cardiac counseling and rehabilitation: a controlled trial.

OBJECTIVES This study evaluated the effectiveness of cardiac counseling and rehabilitation programs led by a nurse counselor, compared with normal care on outcomes for myocardial infarction (MI) patients and their partners. METHODS A randomized controlled trial with follow-up to 1 year was conducted with 100 patients recruited within 72 hours of a first MI and their partners: a Control group received normal care; an Inpatient group received cardiac rehabilitation from a nurse counselor while in hospital; and an Extended group received the same cardiac rehabilitation as the Inpatient group, but with additional sessions continuing up to 6 weeks after discharge from hospital. The scales for main outcome measures were 1) knowledge of heart disease and treatment (correct, misconceptions, and uncertainty); 2) mood (Hospital Anxiety and Depression Scale); 3) satisfaction; 4) disability (Functional Limitations Profile). RESULTS Inpatient cardiac counseling and rehabilitation resulted in more knowledge, less anxiety, less depression, and greater satisfaction with care in both patients and partners and in less disability in patients, with effects enduring to 1 year. There was some evidence of additional benefit from the Extended program. Both nurse counselors achieved benefits on all outcome variables. CONCLUSIONS This Inpatient cardiac counseling and rehabilitation program resulted in significant and enduring benefits of clinical value. It is likely that it would be acceptable to most post-MI patients, many of whom are not offered or are unable to accept outpatient cardiac rehabilitation.

Recovery from disability after stroke as a target for a behavioural intervention: results of a randomized controlled trial.

Purpose. Disability following stroke is highly prevalent and is predicted by psychological variables such as control cognitions and emotions, in addition to clinical variables. This study evaluated the effectiveness of a workbook-based intervention, designed to change cognitions about control, in improving outcomes for patients and their carers. Method. At discharge, stroke patients were randomly allocated (with their carers) to a 5-week intervention (n = 103) or control (normal care: n = 100). The main outcome (at 6 months) was recovery from disability using a performance measure, with distress and satisfaction as additional outcomes. Results. The intervention group showed significantly better disability recovery, allowing for initial levels of disability, than those in the control group, F(1,201) = 5.61, p = 0.019. Groups did not differ in distress or satisfaction with care for patients or carers. The only psychological process variable improved by the intervention was Confidence in Recovery but this did not mediate the effects on recovery. Conclusions. A large proportion of intervention participants did not complete the workbook tasks. This was perhaps associated with the fairly low level of personal contact with workbook providers. The modest success of this intervention suggests that it may be possible to develop effective behavioural interventions to enhance recovery from disability in stroke patients.

Problems with the sickness impact profile: a theoretically based analysis and a proposal for a new method of implementation and scoring.

The Sickness Impact Profile (SIP) is one of the most widely used health status measures, but there are problems with the measure that lead to inconsistent and illogical scores. There are many desirable features to the SIP development methodology in that it is based on a good range of items and the item weightings are valuable. The current method of scoring the SIP is the use of a summated total and was selected based on limited empirical evidence. However, in this paper we argue that there are problems with the SIP because the current empirically derived method of scoring is incompatible with both the underlying theoretical scaling framework (Thurstone scaling) and the nature of the items in the SIP. In addition, the items do not have properties consistent with the scaling methodology. We suggest that it is crucial to take both a theoretical and empirical approach to selecting a scoring method. To examine problems associated with the SIP we explored the underlying scaling methodology and identified the types of items in the SIP. A new method of scoring is proposed that is consistent with the items and scaling in the SIP, namely using the maximum individual weighting from the items that were checked as a category score. This new method of scoring resolves many of the previously observed problems in the SIP. The new method of scoring also presented the opportunity for a new implementation of the SIP that reduces the number of items that most respondents, especially those with severe limitations, would be asked. Without taking a theoretical approach to scoring we suggest that subsequent, empirically based, scale amendments are unlikely to solve the problems. It is proposed that this new method of scoring justifies a thorough empirical investigation.

Consequences of disease: testing the WHO International Classification of Impairments, Disabilities and Handicaps (ICIDH) model.

The International Classification of Impairments, Disabilities and Handicaps (ICIDH) model proposes that there are three consequences of disease, impairment (I), disability (D) and handicap (H) and that they are sequentially related. This paper examines first, whether I, D and H can be measured independently and second, whether there is support for the sequential or causal relationship between the three constructs. Cross-sectional data from a representative sample of 101 disabled adults and longitudinal data from 108 myocardial infarction (MI) and 68 Stroke patients were used. Standard measures of I were used for each clinical condition. Measures of D and H were derived from the British version of the Sickness Impact Profile (SIP) and additional measures of D were available for the Stroke group. Judges classified SIP items according to ICIDH definitions of D and H. Correlation, Confirmatory Factor Analyses and Path Analyses were used to examine the main hypotheses. Valid measures of D and H were derived and there was evidence of separation of the three constructs for the Stroke patients but not for the other groups. For both Stroke and MI, I was not predictive of D and H. For Stroke, the best path model included a path from D to H, but not from H to D and this was found for self-report and performance measures of D. Using these measures, the ICIDH model was supported in that D predicted H for stroke, but there was no support for a path between I and D or between I and H. Further it was not always possible to distinguish the three constructs. Possible limitations in the measures and in the ICIDH model as a testable scientific model are discussed.

Exploring the relationships between International Classification of Functioning, Disability and Health (ICF) constructs of Impairment, Activity Limitation and Participation Restriction in people with osteoarthritis prior to joint replacement

BackgroundThe International Classification of Functioning, Disability and Health (ICF) proposes three main constructs, impairment (I), activity limitation (A) and participation restriction (P). The ICF model allows for all paths between the constructs to be explored, with significant paths likely to vary for different conditions. The relationships between I, A and P have been explored in some conditions but not previously in people with osteoarthritis prior to joint replacement. The aim of this paper is to examine these relationships using separate measures of each construct and structural equation modelling.MethodsA geographical cohort of 413 patients with osteoarthritis about to undergo hip and knee joint replacement completed the Aberdeen measures of Impairment, Activity Limitation and Participation Restriction (Ab-IAP). Confirmatory factor analysis was used to test the three factor (I, A, P) measurement model. Structural equation modelling was used to explore the I, A and P pathways in the ICF model.ResultsThere was support from confirmatory factor analysis for the three factor I, A, P measurement model. The structural equation model had good fit [S-B Chi-square = 439.45, df = 149, CFI robust = 0.91, RMSEA robust = 0.07] and indicated significant pathways between I and A (standardised coefficient = 0.76 p < 0.0001) and between A and P (standardised coefficient = 0.75 p < 0.0001). However, the path between I and P was not significant (standardised coefficient = 0.01).ConclusionThe significant pathways suggest that treatments and interventions aimed at reducing impairment, such as joint replacement, may only affect P indirectly, through A, however, longitudinal data would be needed to establish this.

What does the chronic pain grade questionnaire measure

Abstract This study explored the ability of the Chronic Pain Grade Questionnaire (CPG) to operationalise the WHO’s model of health outcomes, namely the International Classification of Functioning, Disability and Health (ICF). Twelve expert judges used the method of discriminant content validation to allocate the seven items of the CPG to one or more ICF outcome, namely, impairment, activity limitations and participation restrictions. One‐sample t‐tests classified each item as measuring impairment, activity limitations or participation restrictions, or a combination thereof. The results indicated that the CPG contains items able to measure each of the three ICF outcomes. However, the pain grade classification system used in the CPG conflates the ICF outcomes. The implication of this conflation of outcome for the assessment of interventions is discussed.

Using the ICF and psychological models of behavior to predict mobility limitations

Aims to test the ability of a model that integrates the theory of planned behavior (TPB) into the International Classification of Functioning Disability and Health (ICF) to predict walking limitations in adults awaiting hip or knee replacement surgery. Study Design and Participants: Cross-sectional structural equation modeling study of activity limitations in 190 adults. Method: A postal questionnaire measuring the TPB, ICF and walking limitations. Results: The integrated model accounted for more variance in activity limitations (57%) than either the TPB or ICF alone. Control beliefs (TPB) significantly mediated the relationship between impairment (ICF) and activity limitations. Conclusions: The integrated model provides an interdisciplinary theoretical framework that identifies intervention targets to effect reductions in disability without the need for concomitant reductions in impairment.

Perceived control and recovery from functional limitations : Preliminary evaluation of a workbook-based intervention for discharged stroke patients

Background. Previous research has demonstrated that control cognitions predict functional limitations following stroke. This paper reports a preliminary evaluation of the effects of a workbook intervention, designed to enhance perceptions of control, in reducing disability in patients discharged from hospital following stroke. Methods. Thirty-nine patients living at home who had had a stroke within the 2 previous years completed baseline assessments of functional limitations, mood and perceived control. They were then randomly allocated to either a Workbook Intervention or a Wait control group and functional limitation and mood outcomes were assessed 1 month later. Results. Results showed no benefit of the intervention, but both groups showed reduced functional limitations. Reductions in functional limitations were correlated with increases in perceptions of control. Conclusions. Clearly, the workbook intervention needs to be strengthened before a full evaluation would be worthwhile for this clinical group. It is possible that both groups demonstrated spontaneous recovery or may have benefited from the additional attention given by the researcher. These benefits were associated with enhanced perceptions of control, contributing to previous findings suggesting that control cognitions may be both a consequence and a determinant of functional limitations.