Screening for Depression in cADiovasCular pAtients at a Tertiary Center in Trinidad.

The study design was a cross-sectional descriptive study performed from November 2018 to February 2019. It was performed at the Eric Williams Medical Sciences Complex, Champ Fleurs, Trinidad. The primary objectives of the study were to screen patients for depression in those with cardiovascular disease in Trinidad and Tobago and to determine the association between patients with depression and other comorbidities.

Patients were targeted for participation in the study while waiting to see the attached physician to the cardiology clinic. Participants were attained at the Eric Williams Medical Sciences Complex during the days Monday to Friday where there were ongoing cardiology outpatient clinics. Once informed consent was obtained from these patients, a questionnaire was administered to these patients in which the primary investigator and/or co-investigator was/were present on site. The number of participants in this study was 1203 patients. There were no dropped subjects from the study nor were there any incomplete questionnaires by any participants. The sample size for this study was calculated to be 1159 patients. Based on a study done by Huffman, it was estimated that 40% of patients with cardiovascular disease also have depression(2). The Type I error rate 5% (α = 0.05) making the Type II error rate 95% (β = 0.95) with a statistical power of 90%. Assuming a 10% patient decline and attrition rate and a minimum detectable difference of 10%, the estimated sample size was calculated to be 1159 patients.

Data collection was performed by the researchers of the study along with eight specifically trained and oriented medical students. All data collectors in the study were supervised by primary investigator and co-investigator of the study so that in the event of any adverse events such as acute psychosis or any acute cardiology emergencies, patients could have been referred directly to the accident and emergency department at Eric Williams Medical Sciences Complex where routine medical care could have been executed.

Additionally, there was an attached consent form which was also approved by the ethical committee of the University of the West Indies, St. Augustine. This consent form clearly explained to the participants why the research was being conducted, the average duration of completing the questionnaire, the benefits and any potential risks associated with participation in the study along with the assurance that confidentiality will be maintained throughout the entire study and that the patient can stop or not complete the questionnaire at any point without any facing repercussions. This information was documented on the consent form and also explained by the researchers of the study to each potential participant. All additional questions from patients were answered truthfully regardless of if it would have affected the patient's decision to participate in the study.

Patients were asked to participate in the study as long as they were registered patients at Eric Williams Medical Sciences Complex in any of the cardiology outpatient clinics. This was confirmed by matching patients with their registration numbers on the cardiology outpatient clinic appointment listings. These lists are made prior to each cardiology clinic that is scheduled every week on Mondays, Tuesdays, Wednesdays, Thursdays and Fridays. The inclusion criteria for participation in the study included patients who were 18 years old and over along with registered patients of the cardiology outpatient clinics at Eric Williams Sciences Complex.