Martínez Alvarez J M, Marijuán Arcocha L, Retolaza Balsategui A, Duque Valencia A, Cascán Martín J M
Equipo de Atención Primaria de Basauri, Vizcaya.
Aten Primaria. 1993 Feb 28;11(3):127-32.
To calculate the probable prevalence of mental illness in our clinics and to evaluate how it is detected by Primary Care (PC) doctors.
Crossover study in two parts. SITE. Basauri Health Centre (Vizcaya).
A sample made up of patients who attended the clinic without prior appointment during ten days in February and Marc, 1990.
In the first part, 10 PC doctors distributed the GHQ-28 questionnaire to 500 patients. In the second part, qualified staff administered the standardised psychiatric interview (SPI) to a sub-sample. 41.55% were possible psychiatric cases (GHQ-28 > 6). 17.94% were diagnosed by the doctors (SD) as psychiatric cases. Prevalences adjusted to the SPI were 19% and 21% for the GHQ-28 and SD respectively.
The GHQ-28 obtained high sensitivity (0.82%) and low specificity (60%), which characterises it as a good screening test, but a bad diagnostic method. The doctors obtained low sensitivity (0.29) and high specificity (89.7%); thus underdiagnosing mental illness, but being more accurate in their diagnoses.
