Call for overhaul of 'inconsistent' depression scores
By Lilian Anekwe
Depression severity scores used by GPs perform ‘inconsistently in practice' and should have their thresholds for diagnosis raised, leading academics have concluded.
Their study, published online by the BMJ, found the PHQ-9 tool diagnosed 50% more patients as moderately or severely depressed than the hospital anxiety and depression scale.
But the researchers warned that neither scores had much credibility with GPs and that both needed new, more conservative cut-offs that would better reflect clinical practice.
In total, the records of 2,294 patients at 38 GP practices were assessed using one of three depression severity questionnaires – the PHQ-9, HADS or the Beck depression inventory.
Some 83.5% of patients were classified as moderately to severely depressed by the PHQ-9 tool, compared with 55.7% using the HADS tool. The number of patients assessed by the Beck tool was too small for analysis.
But the proportion of patients referred to specialists was only marginally higher with PHQ-9 than HADs – at 23.7% versus 20.4% - suggesting GPs took little notice of the scores.
Older patients were less likely to be referred than younger ones, and patients with diabetes, CHD or other chronic illnesses were treated and referred less often than those without a chronic illness.
Study leader Professor Tony Kendrick, a GP and professor of primary medical care at the University of Southampton, told Pulse GPs tended to discount depression detected through screening and were unwilling to label patients who were not complaining of depression.
‘The PHQ-9 and HADS perform inconsistently in practice and it may be that changing recommended threshold scores for intervention might make the measures more valid, more consistent with GPs' clinical judgement and more acceptable to GPs as a way of classifying patients.
He added: ‘Older patients were less likely to be referred, which is in line with previous research suggesting under-treatment, recently highlighted by Age Concern.'
In response to the findings Age Concern has launched an online tool called ‘Take the Challenge' to improve the detection and treatment of depression in older patients by GPs in collaboration with the RCGP.
Dr Carolyn Chew-Graham, RCGP clinical champion of mental health, said: ‘We would like to see primary care staff learning more about depression in older people.'Research into depression scoring tools shows they lead to inconsistencies in practice