Isobel M. Cameron

Measuring depression severity in general practice: discriminatory performance of the PHQ-9, HADS-D, and BDI-II

BACKGROUND The UK Quality and Outcomes Framework (QOF) rewards practices for measuring symptom severity in patients with depression, but the endorsed scales have not been comprehensively validated for this purpose. AIM To assess the discriminatory performance of the QOF depression severity measures. DESIGN AND SETTING Psychometric assessment in nine Scottish general practices. METHOD Adult primary care patients diagnosed with depression were invited to participate. The HADS-D, PHQ-9, and BDI-II were assessed against the HRSD-17 interview. Discriminatory performance was determined relative to the HRSD-17 cut-offs for symptoms of at least moderate severity, as per criteria set by the American Psychiatric Association (APA) and NICE. Receiver operating characteristic curves were plotted and area under the curve (AUC), sensitivity, specificity, and likelihood ratios (LRs) calculated. RESULTS A total of 267 were recruited per protocol, mean age = 49.8 years (standard deviation [SD] = 14.1), 70% female, mean HRSD-17=12.6 (SD = 7.62, range = 0-34). For APA criteria, AUCs were: HADS-D = 0.84; PHQ-9 = 0.90; and BDI-II = 0.86. Optimal sensitivity and specificity were reached where HADS-D ≥9 (74%, 76%); PHQ-9 ≥12 (77%, 79%), and BDI-II ≥23 (74%, 75%). For NICE criteria: HADS-D AUC = 0.89; PHQ-9 AUC = 0.93; and BDI-II AUC = 0.90. Optimal sensitivity and specificity were reached where HADS-D ≥10 (82%, 75%), PHQ-9 ≥15 (89%, 83%), and BDI-II ≥28 (83%, 80%). LRs did not provide evidence of sufficient accuracy for clinical use. CONCLUSION As selecting treatment according to depression severity is informed by an evidence base derived from trials using HRSD-17, and none of the measures tested aligned adequately with that tool, they are inappropriate for use.

A cost comparison of hysterectomy and hysteroscopic surgery for the treatment of menorrhagia

OBJECTIVES To estimate and compare the costs of treating women with menorrhagia by hysterectomy or hysteroscopic surgery, in the form of transcervical resection of the endometrium (TCRE) or endometrial laser ablation (ELA). STUDY DESIGN Randomised controlled trial set in the gynaecological department of a large British teaching hospital. Under usual circumstances, 204 women who would have undergone hysterectomy for menorrhagia were randomly allocated to either hysterectomy (n = 99) or hysteroscopic surgery in the form of TCRE (n = 52) or ELA (n = 53). National Health Service (NHS) costs and costs to patients per patient occurring up to 1 year following surgery were estimated. Theatre times and length of hospital stay were recorded during the trial. Costs were obtained from the health board finance department and relevant suppliers of technical equipment. One year after treatment patients completed questionnaires on personal costs incurred. RESULTS The NHS costs of treating women with hysteroscopic surgery were 24% (TCRE) or 20% (ELA) less than treating women by hysterectomy (1001 pounds/1046 pounds vs. 1315 pounds). On average, women undergoing hysteroscopic surgery incurred 71% less costs to themselves than those who underwent hysterectomy (21 pounds vs. 73.40 pounds). CONCLUSIONS Hysteroscopic endometrial ablation incurs less costs than hysterectomy both to the National Health Service and to women alike, up to 1 year after surgery.

Psychometric properties of the BASIS-24© (Behaviour and Symptom Identification Scale–Revised) Mental Health Outcome Measure

Objective. Outcome measurement in mental health services is an area of considerable clinical interest and policy priority. This study sought to assess the Behaviour and Symptom Identification Scale-24 (BASIS-24©), a brief, patient self-reported measure of psychopathology and functioning, in a UK sample, including establishing population norms for comparative purposes. Methods. Participants were 588 adults recruited from psychiatric inpatient, outpatient and primary care settings; and 630 adults randomly sampled from primary care lists who completed the BASIS-24©, and the Brief Symptom Inventory (BSI) at two time points. Results. BASIS-24© demonstrated adequate reliability (coefficient α values for combined clinical sample across subscales ranged from 0.75 to 0.91), validity and responsiveness to change (effect size for change of the BASIS-24© was 0.56 compared with 0.48 for BSI Global Severity Index). Population norms were established for the general population and adult in-patients (at in-take). The scale proved straightforward to complete across clinical settings. Variable rates of questionnaire distribution across clinical settings highlighted the ongoing challenge of incorporating outcome measures in clinical settings. Conclusion. BASIS-24© is a brief, easily administered, self-complete measure of mental well-being and functioning that adequately meets the requirements of reliability, validity and responsiveness to change required of an outcome measure.

Psychometric properties of the 16-item Quick Inventory of Depressive Symptomatology: A systematic review and meta-analysis

Effective management of depression is predicated upon reliable assessment. The Quick Inventory of Depressive Symptomatology (QIDS) is a depression severity scale with both self-rated (QIDS-SR16) and clinician-rated (QIDS-C16) versions. Although widely used in research, the psychometric properties of the QIDS16 have not been systematically reviewed. We performed a systematic review of studies of the psychometric properties (factor structure, internal consistency, convergent validity, discriminant validity, test-retest reliability and responsiveness to change) of the QIDS-SR16 or QIDS-C16. Six databases were searched: MEDLINE, EMBASE, PsycINFO, CinAHL, Web of Science and the Cochrane Central Register of Controlled Trials. Findings were summarised, bias assessed and correlations with reference standards were pooled. 37 studies (17,118 participants) were included in the review. Both versions of the QIDS16 were unidimensional. Cronbachs alpha ranged from 0.69 to 0.89 for the QIDS-SR16 and 0.65 to 0.87 for the QIDS-C16. The QIDS-SR16 correlated moderately to highly with several depression severity scales. Seven studies were pooled where QIDS-SR16 was correlated with the HRSD-17 (r = 0.76, CI 0.69, 0.81) in patients diagnosed with depression. Four studies examined convergent validity with the QIDS-C16. Four studies examined discriminant validity, for the QIDS-SR16 alone. Eighteen studies had at least one author who was a co-author of the original QIDS16 study. Most studies were conducted in the USA (n = 26). The QIDS-SR16 and the QIDS-C16 are unidimensional rating scales with acceptable internal consistency. To justify the use of the QIDS16 scale in clinical practice, more research is needed on convergent and discriminant validity, and in populations outside the USA.

Comparison of consultation rates in primary care attenders with and without seasonal affective disorder

BACKGROUND There is a lack of published information about the consultation patterns of patients with seasonal affective disorder (SAD) in primary care, when compared with non-seasonal controls (NSCs). METHODS Interview-confirmed SAD cases (n=90) were age- and sex-matched to two controls without significant seasonal morbidity on the Seasonal Pattern Assessment Questionnaire (SPAQ) (non-seasonal controls, NSCs). A comparison of their consultation rates was made using data abstracted from primary care records over 4 years. RESULTS The monthly rate of general practice consultations for SAD cases was significantly higher than that for NSCs. There was a significant difference in the median number of consultations in winter and autumn between the two groups. The matched multivariate analysis revealed that February and April were the independent months in which cases of SAD had significantly more consultations than NSCs. LIMITATIONS Optimal diagnostic criteria for SAD have not been determined and our criteria may have been over-inclusive. CONCLUSION In addition to a marked difference in monthly consultation rates between SAD cases and NSCs, the data demonstrate a difference in the pattern of seasonality of these rates. It is possible that increased frequency of consultation, in particular during the winter months (in patients who score as a case SPAQ), could be used as an indication of SAD in primary care.

A comparison of three methods of assessing differential item functioning (DIF) in the Hospital Anxiety Depression Scale: ordinal logistic regression, Rasch analysis and the Mantel chi-square procedure.

PurposeIt is important for clinical practice and research that measurement scales of well-being and quality of life exhibit only minimal differential item functioning (DIF). DIF occurs where different groups of people endorse items in a scale to different extents after being matched by the intended scale attribute. We investigate the equivalence or otherwise of common methods of assessing DIF.MethodThree methods of measuring age- and sex-related DIF (ordinal logistic regression, Rasch analysis and Mantel χ2 procedure) were applied to Hospital Anxiety Depression Scale (HADS) data pertaining to a sample of 1,068 patients consulting primary care practitioners.ResultsThree items were flagged by all three approaches as having either age- or sex-related DIF with a consistent direction of effect; a further three items identified did not meet stricter criteria for important DIF using at least one method. When applying strict criteria for significant DIF, ordinal logistic regression was slightly less sensitive.ConclusionsOrdinal logistic regression, Rasch analysis and contingency table methods yielded consistent results when identifying DIF in the HADS depression and HADS anxiety scales. Regardless of methods applied, investigators should use a combination of statistical significance, magnitude of the DIF effect and investigator judgement when interpreting the results.

Differential item functioning of the HADS and PHQ-9: an investigation of age, gender and educational background in a clinical UK primary care sample.

BACKGROUND The Patient Health Questionnaire (PHQ-9) and Hospital Anxiety and Depression Scale (HADS) are commonly used measures in clinical practice and research. It is important that such scales measure the trait they purport to measure and that the impact of other measurement artefacts is minimal. Differential item functioning of these scales by gender, educational background and age is currently assessed. METHODS Severity of depression and anxiety symptoms were measured in primary care patients referred to mental health workers using the PHQ-9 and HADS. Each scale was assessed for Differential Item Functioning (DIF) and Differential Test Function (DTF) by gender, educational background and age. Minimum n per analysis=895. DIF was assessed with Mantels χ(2), Liu-Agresti cumulative common odds ratio (LA LOR) and the standardised LA LOR (LA LOR-Z). DTF was assessed in relation to ν(2). RESULTS PHQ-9, HADS Depression Sub-scale (HADS-D) and HADS Anxiety Subscale (HADS-A) lacked bias in terms of gender and educational background (ν(2)<0.07). However, both PHQ-9 and HADS-D exhibited bias with regard to age: PHQ-9 ν(2)=0.103 (medium effect); HADS-D ν(2)=0.214 (large effect). PHQ-9 items exhibiting DIF by age covered: anhedonia, energy and low mood. HADS-D items exhibiting DIF by age covered psychomotor retardation and interest in appearance. LIMITATIONS No assessment of other potential DIF contributors was made. CONCLUSIONS PHQ-9, HADS-D and HADS-A generally do not exhibit bias for gender and educational background. However bias was observed in PHQ-9 and HADS-D for age. Caution should be exercised interpreting scores both in clinical practice and research.

Admission-discharge policies for hysteroscopic surgery: a randomised comparison of day case with in-patient admission.

OBJECTIVE To study the effectiveness and acceptability of day case hysteroscopic surgery. DESIGN Prospective randomised controlled trial. SETTING Aberdeen Royal Infirmary. SUBJECTS One hundred and ninety four consecutive women who underwent hysteroscopic endometrial ablation. INTERVENTION Seventy three women were allocated to day case surgery and 37 to inpatient admission; 84 women though otherwise fit for day case surgery were scheduled for in-patient admission as they lived more than 20 miles away. All women completed a questionnaire 24 h after their operations. Readmission rates were obtained from case notes. Satisfaction rates 12 months after the operation were recorded by means of a follow-up questionnaire. RESULTS Post-operative pain was absent or slight in 48 (75%) of the women in the day case group 27 (84%) of women in the in-patient group, and 55 (82%) in the non-randomised in-patient group. Post-operative analgesia was necessary in 34 (52%) women in the day case group, 24 (75%) women in the in-patient group and 36 (53%) women in the non-randomised in-patient group. Hospital costs were significantly less in the day case group. Satisfaction with stay 92% in the day case group, and 100% in the other two groups. CONCLUSION In this setting, day care is a safe acceptable and less expensive alternative to in-patient care for hysteroscopic endometrial ablation.

Why do patients discontinue antidepressant therapy early? A qualitative study

Abstract Background: Current guidelines for antidepressant prescribing are that treatment should be continued following the resolution of symptoms: six months after a first episode and for at least two years for those with previous episodes. Despite this, sub-optimal treatment duration still predominates. Patients have negative and positive views on antidepressants, which change throughout their treatment journey. Objectives: To explore views and experiences of patients recently initiated on antidepressants (within six months), and to consider the influences on early discontinuation. Methods: A qualitative interview study was used in four general practices in the North East of Scotland. A purposive sample of primary care patients, newly initiated on antidepressants, was interviewed to explore views and experiences with antidepressant therapy. Interviews were audio-recorded and transcribed verbatim. Thematic analysis was conducted using a consensus coding frame developed by two researchers. Results: Twenty-nine patients participated. Three main factors influencing discontinuation were identified: ownership, knowledge and support. The treatment journey was characterized by four important time points where health care intervention may be helpful. Conclusion: Health care professionals would benefit from exploring patient knowledge and views on depression and antidepressants at an early stage in treatment. Patients would welcome active involvement in treatment decision making, the provision of information and ongoing support.

Efficacy and tolerability of antidepressants for sub-threshold depression and for mild major depressive disorder

BACKGROUND It is commonly assumed that robust evidence exists for the lack of efficacy of antidepressants at the milder end of the depression severity spectrum. In light of specific limitations of existing reviews, we assess if antidepressants are efficacious and tolerable for sub-threshold or mild major depressive disorder (MDD). METHOD Systematic review and meta-analysis of randomised controlled trials of adults with sub-threshold depression or mild MDD (initial baseline symptom severity of HRSD≤20) comparing an antidepressant with placebo or treatment as usual (TAU) however defined. A pre-specified protocol was published (Prospero reference: CRD42013004505). RESULTS 8 trials were included: 5 trials (453 participants) of sub-threshold depression and 3 trials (502 participants) of mild MDD. Trials of sub-threshold depression exhibited low risk of bias whereas those of mild MDD exhibited high risk. Two trials of sub-threshold depression were pooled (n=102) to assess efficacy and favoured antidepressants over placebo statistically but the difference was small and unlikely to be clinically meaningful: mean difference -1.39 (-2.41, -0.36). Due to heterogeneity, no trials of mild MDD could be pooled for efficacy. There was no difference between antidepressant treatment and placebo for drop out due to adverse events. The maximum proportion in those receiving antidepressants dropping out due to adverse events was 17%, with indication of a dose effect. LIMITATIONS Not all data from identified trials could be included in the meta-analyses due to a lack of availability of relevant data. CONCLUSION There is insufficient evidence to support or contest the efficacy of antidepressant medication for sub-threshold depression or mild MDD. More trials, with adequate follow up, are required to address this question.