Sex difference in using the SCOFF questionnaire to identify eating disorder patients at a psychiatric outpatient clinic

Abstract

Objective

Patients with eating disorder (ED) often remain unrecognized in many settings. Few studies have explored the use of eating measures in an adult male population. This study aimed to examine the comparative validity of the SCOFF questionnaire for detecting ED cases in men and women in the psychiatric outpatient setting.

Method

Psychiatric outpatients, including 605 men and 936 women, aged 18–45 years, completed the paper form SCOFF and were interviewed using the ED Module of the Structured Clinical Interview for the DSM-IV-TR. A subgroup of patients completed several additional self-reported questionnaires concerning eating and general psychopathology.

Results

Scores of 2 and 3 on the SCOFF were the optimal cutoff values for determining ED among men (sensitivity 86% and specificity 74%) and women (sensitivity 80% and specificity 86%), respectively. While age did not significantly affect the validity indices, the SCOFF as a screening tool for ED in obese men was underperformed.

Conclusions

The Mandarin Chinese version of the SCOFF is a potentially valid tool to detect ED in both genders in the psychiatric outpatient settings. By helping to detect hidden ED morbidity, the SCOFF can enhance diagnostic accuracy and facilitate comprehensive treatment among psychiatric outpatients.

Introduction

In past decades, reports of eating disorders (EDs) have increased in non-Western countries [1]. Community-based studies show that the prevalence of ED in Asia is now comparable to that in Western society [2], [3]. Frequent comorbidities with other psychiatric disorders and medical conditions as well as the associated functional impairments make ED an important mental health issue [4]. Previous studies have highlighted the need for early diagnosis and intervention to improve the prognosis of EDs [5]. Notably, those with a diagnosis of ED are usually more aware of co-occurring general mental health problems or medical conditions than eating problems per se [6], [7]. Most patients with EDs remain unrecognized in the primary care settings or general mental health settings [8].

Recent studies indicate that EDs are prevalent in young patients presenting to the emergent department of a tertiary medical center or Anxiety and Depression Program at a mental health outpatient clinic [8], [9]. In contrast to earlier impressions, a recent study suggested that individuals with disordered eating may be quite amenable to disclosing symptoms in clinical settings and that questions asked about ED may enhance detection and facilitate treatment [10]. Since current diagnostic tools for EDs are very cumbersome to administer and often require specialist interpretation, a brief and easily interpreted measure is needed to detect hidden ED cases in time-constrained settings such as general psychiatric outpatient clinics.

The SCOFF, developed by Morgan et al., is a brief and simple screening instrument comprising five dichotomous questions regarding binge eating, purging, and body dissatisfaction [11]. At a cut-off score of 2, the estimated sensitivity of the SCOFF for detecting EDs in community samples ranges from 53 to 95%, and the estimated specificity ranges from 88 to 95% [12], [13], [14]. The corresponding figures reported in clinical population in primary care clinics range from 72 to 85% and from 73 to 89%, respectively [15], [16], [17]. Nevertheless, most validation studies have been performed in small samples comprised exclusively of females, and only a few studies were conducted in psychiatric samples [8], [18].

Eating disorders, e.g., anorexia nervosa (AN) and bulimia nervosa (BN), are much more prevalent in females than males [19]. Notably, the gender difference is smaller in the most recently defined binge eating disorder (BED) [20]. Studies found the lower help-seeking rates of men might be explained by that men are more reluctant to discuss their eating problems openly or that health care providers are less likely to accurately detect ED in male patients [20]. Few studies have explored the utility of an eating measure in adult male populations. Only one study has reported SCOFF screening had no gender difference in young students [21].

The aim of the present study was to examine the comparative validity of the SCOFF questionnaire in both men and women in the general psychiatric outpatient setting. Specifically, we considered whether diagnostic validity varied by gender in terms of age and body mass index (BMI). The BMI was of special interest because of reports that BMI affects the validities of several eating-related measures, including the SCOFF [15].