Validation of Persian translation of ‘The Liverpool Adverse Event Profile (LAEP): An Instrument for Measuring Adverse Effects of Antiepileptic Drugs

Liverpool adverse event profile (LAEP) was developed in 1994 and validated among patients with epilepsy in the UK,[1 ] and was later translated and validated in some other languages such as Spanish, Chinese, Korean, Italian, Portuguese-Brazilian, Arabic and Bulgarian[2-8 ] and has been used in numerous studies.[5 , 6 , 9-23 ] As yet, this important instrument has not been validated in the Persian language. LAEP questionnaire is patient-centered, and is concerned with general questions.Due to the significance of the questionnaire in both clinical analysis of the patient-reported AEs and in conducting relevant researches,the researchers decided to have an investigation into its reliability and validity in our native language (i.e., Persian) in order to use it with Persian speaking patients. In fact, this study is intended to validate the Persian translation of the Liverpool adverse event profile (LAEP). Method: An observational, and cross-sectional design was utilized to study patients suffering from epilepsy and treated with a stable dose of AEDs. The instrument was translated from the English version into Persian to examine its overall accuracy. To that end,the Persian LAEP (hereafter called p-LAEP) was administered to 140 patients to examine comprehensibility and transparency of the language and instructions. Further, the researchers used the patients’ and specialists’ comments to assess its construct validity. Next, using a qualitative-quantitative approach, the content validity ratio (CVR) and content validity index (CVI) were calculated to examine the overall validity of this scale.[24 ] Also, the reliability of the instrument was assessed through Cronbach’s alpha coefficient. Results: Bearing in mind the widely used statistical cut off points, we decided the acceptability of validity of all items with CVI and reliability of Cronbach’s ɑ coefficient to be over 0.79 and 0.7, respectively. Baseline ratio for CVR varies proportional to the number of participants. On the whole, the analysis demonstrated a reasonable content validity ratio (as shown in tables in the text), with the reliability (Cronbach’s ɑ coefficient) being 0.79. Conclusion: Overall, the results suggest that p-LAEP is an appropriate instrument to measure adverse effects of antiepileptic drugs among Persian speaking patients with epilepsy.

Keywords:

Reliability , validity , Liverpool Adverse Event Profile/p-LAEP , adverse effects of antiepileptic drugs.