Abstract
Purpose: :
The high prevalence and disabling nature of clinical depression has led to the development of screening tests that can be incorporated into primary care practice settings. To encourage use, the trend has been toward short, simple survey tools such as the Patient Health Questionnaire 2 (PHQ-2), which consists of only two items - one related to mood and the other to anhedonia. This instrument has been employed in studies of various clinical populations, but not in a primary eye care setting, the aim of the current investigation (Gilbody et al, 2007).
Methods: :
The PHQ-2 was included in a written 10-question survey that was administered over a 2-month period to patients seated in the waiting area of the Primary Care Clinic at the University Eye Center of SUNY Optometry. The 8 additional items related to demographics, general and ocular health, concern about going blind, and exercise, relationship, and employment status. Patients placed completed surveys, which included no identifying information, into an unmarked envelope.
Results: :
Surveys were completed by 739 subjects, about 69% of those solicited. 52% of the sample was 46 years of age or older. 64% of subjects were female, and 38% self-identified as Caucasian, 31% Black, 16% Hispanic, 9% Asian, 6% mixed and 1% Native American. The PHQ-2 is scored on a scale of 0 - 6, with higher scores more indicative of depression. Cutoff scores of 2, 3, and 4 resulted, respectively, in 29%, 13% and 7% of subjects failing. Scores were significantly correlated (Pearson two-tailed) with the number of self-reported general health conditions (r = 0.185; p = 0.000), worry about going blind (r = 0.182; p = 0.000) and lack of exercise (r = 0.127; p = 0.001), but not with age (r = -0.066; p = 0.075) or number of self-reported ocular conditions (r = 0.044; p = 0.228).
Conclusions: :
In a sample derived from primary-care and obstetrics-gynecology clinics that had a 7% prevalence of depression as determined using structured clinical interviews, Kroenke et al (2003) found that 15.2% scored 3 or higher, the standard cutoff value on the PHQ-2. Using this same cutoff score, 13% of our sample failed the PHQ-2, pointing to a lower, yet clinically significant, prevalence of depression in the primary eye-care population. Despite its relatively high specificity, most patients who fail the PHQ-2 will not meet the diagnostic criteria for major depression (Mitchell and Coyne, 2007). To prevent over-referral for psychiatric services, the eye-care provider may follow up failing PHQ-2 screening scores by asking the patient additional questions based on DSM-IV diagnostic criteria or administering a more comprehensive screening tool (e.g., Beck Depression Inventory).
Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • clinical (human) or epidemiologic studies: risk factor assessment • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials