Methods
We reviewed cases of ADR previously identified in a study including 300
adult inpatients. These patients were recruited from January 26 to March
6, 2015 in surgical and medical wards of a general 500-bed university
hospital located in Belo Horizonte, Southeastern Brazil. The study was
approved by the Research Ethics Committee of the Universidade Federal de
Minas Gerais. All participants signed a patient consent statement. In
the present study, ADR was defined as “a response to a medicinal
product which is noxious and unintended and which occurs at doses
normally used in man for the prophylaxis, diagnosis or therapy of
disease or for the restoration, correction or modification of
physiological function”, according to WHO.[8, 9] The methods used
to identify ADR were described elsewhere.[9]
Three healthcare professionals acted as judges to adjudicate,
independently, each ADR reported in the study according causality
categories of ADR. The professionals had experience in assistance and
research. They had different academic background, including a nurse
(Judge A), a pharmacist (Judge B) and a physician (Judge C).
Standardized forms were evaluated by the judges and included the
following information: patient’s data (age, sex, diagnosis, type of
comorbidities, laboratory data, daily clinical data and drug therapy)
and ADR data (onset/end of clinical manifestation, history of allergies,
administered doses, drug interactions, suspected drugs to cause ADR and
time of its use).
Expert adjudication process consisted in the evaluation of cases by each
judge, separately, followed by the record of his/her judgment in an
instrument developed specifically for this study. ADR were classified
into six categories (certain, probable, possible, unlikely, conditional,
unassessable), according to WHO-UMC criteria and based on individual
expertise. Additionally, the judge was required to register the
suspected drug(s) to have caused ADR.
ADR causality was also evaluated using Naranjo algorithm which is a
method consisting in ten yes/no questions.[5] They were evaluated in
this study consensually by two clinical pharmacists with
pharmacovigilance expertise. Preventability of ADR was assessed by the
judges, using Schumock and Thornton method, adapted from Shajahanet al. [6, 7]