[1] Univ West Indies, Dept Para Clin Sci, St Augustine Campus, St Augustine 330912, Trinidad Tobago
[2] Morehouse Sch Med, Dept Surg, Atlanta, GA 30310 USA
[3] Eric Williams Med Sci Complex, North Cent Reg Hlth Author, Champs Fleurs 330912, Trinidad Tobago
[4] Univ West Indies, Fac Med Sci, Dept Clin & Surg Sci, St Augustine 330912, Trinidad Tobago