title: Validity of the Center for Epidemiological Studies Depression scale in Type 2 diabetes.
abstract: Depressive symptoms are common among people with Type 2 diabetes mellitus (T2DM). This study aimed to validate the 3-factor structure of the 14-item Center for Epidemiological Studies Depression (CES-D) scale proposed by Carleton et al. (2013) in a T2DM population.
  
  
  
  The CES-D was administered to consecutive patients with T2DM entering a rehabilitation program. Construct validity was assessed using confirmatory factor analysis. Subscale viability, differential item functioning, and associations with clinical characteristics were tested in bifactor models.
  
  
  
  Among adults with T2DM (n=305, age 56.9±11.1, 44.9% male, duration of diabetes 7.8±7.9years, HbA1c 0.076±0.014%), the construct validity of Carleton's 3-factor solution (negative affective, positive affective and somatic symptoms) was confirmed, although negative affective and somatic symptoms were highly correlated (r=0.926). The CES-D items can be summed to arrive at a total score (ωH=0.869), but not subscale scores (ωS>0.7). Differential item functioning was not found based on age or body mass index (BMI), but Item 1 ("I was bothered by things that don't usually bother me") was inflated in women and Item 7 ("I felt that everything I did was an effort") was inflated in those with higher glycosylated haemoglobin (HbA1c). The general depression factor decreased with age (β=-0.247, p<0.001) and increased with BMI (β=0.102, p=0.041) but not HbA1c (β=0.065, p=0.461). Negative affective symptoms (β=0.743, p=0.001), but not other depressive symptoms, were higher in women.
  
  
  
  The 14-item CES-D retained construct validity in adults with T2DM. Depressive symptoms were associated with younger age, female gender and BMI, but not with glycemic control.
authors: University of Toronto, Department of Pharmacology and Toxicology, Canada; Sunnybrook Research Institute, Hurvitz Brain Sciences Centre, Canada; University Health Network Toronto Rehabilitation Institute, Cardiac Rehabilitation Program, Canada. Electronic address: jasmine.carter@mail.utoronto.ca.
authors: Jasmine
authors: J
authors: Carter
authors: Universidade Federal de São Paulo, Department of Psychiatry, Brazil. Electronic address: hugocogobr@gmail.com.
authors: Hugo
authors: H
authors: Cogo-Moreira
authors: University of Toronto, Department of Pharmacology and Toxicology, Canada; Sunnybrook Research Institute, Hurvitz Brain Sciences Centre, Canada. Electronic address: nathan.herrmann@sunnybrook.ca.
authors: Nathan
authors: N
authors: Herrmann
authors: University Health Network Toronto Rehabilitation Institute, Cardiac Rehabilitation Program, Canada. Electronic address: dmmerino@waterloo.ca.
authors: Daniel
authors: D
authors: Merino
authors: University Health Network Toronto Rehabilitation Institute, Cardiac Rehabilitation Program, Canada. Electronic address: pearly.yang@gmail.com.
authors: Pearl
authors: P
authors: Yang
authors: University of Toronto, Department of Health Policy, Canada; Sunnybrook Research Institute, Hurvitz Brain Sciences Centre, Canada. Electronic address: baiju.shah@ices.on.ca.
authors: Baiju R
authors: BR
authors: Shah
authors: University of Toronto, Department of Health Policy, Canada; Sunnybrook Research Institute, Hurvitz Brain Sciences Centre, Canada. Electronic address: alex.kiss@ices.on.ca.
authors: Alex
authors: A
authors: Kiss
authors: University Health Network Toronto Rehabilitation Institute, Cardiac Rehabilitation Program, Canada. Electronic address: jaan.reitav@uhn.ca.
authors: Jaan
authors: J
authors: Reitav
authors: University of Toronto, Department of Pharmacology and Toxicology, Canada; Sunnybrook Research Institute, Hurvitz Brain Sciences Centre, Canada; University Health Network Toronto Rehabilitation Institute, Cardiac Rehabilitation Program, Canada. Electronic address: paul.oh@uhn.ca.
authors: Paul I
authors: PI
authors: Oh
authors: University of Toronto, Department of Pharmacology and Toxicology, Canada; Sunnybrook Research Institute, Hurvitz Brain Sciences Centre, Canada; University Health Network Toronto Rehabilitation Institute, Cardiac Rehabilitation Program, Canada. Electronic address: w.swardfager@utoronto.ca.
authors: Walter
authors: W
authors: Swardfager
mesh_terms: D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D003863:Depression / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology*; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000523:psychology*; D004644:Emotions; D016021:Epidemiologic Studies; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales / Q000592:standards*; D011594:Psychometrics; D012189:Retrospective Studies
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin
keywords: Bifactor model; Center for Epidemiological Studies Depression scale; Depression; Differential item functioning; Glycemic control; Invariance; Type 2 diabetes