Study protocol
Data collection:
The eligible patients will be asked to participate in the study. After signing informed consent, the patients will be asked to complete questionnaire, all clinical and laboratory data of the patients will be retrieved from out-patient electronic or paper medical records, electronic laboratory results. The data will include the followings:
1. Clinical data
* Demographic information (age, gender, ethnicity, education, marital status)
* Family history of liver disease
* Current relevant medication
* Weight, height and body mass index (BMI) at the time of enrollment
* History of blood or blood product transfusion, last transfusion
* History of alcohol consumption
* History of active liver disease
2. Laboratory data
* Complete blood count
* Iron study (serum ferritin, serum iron, total iron binding capacity and transferrin saturation)
* Hemoglobin typing
* HIV antibody status (only if available)
* liver biochemistry including AST, ALT, albumin, globulin
* Blood urea nitrogen, creatinine
* HBsAg, Anti-HBsAb
* Anti-HCV antibody
* HCV RNA, HCV genotyping (only in patients with positive Anti-HCV)
* Serum hyaluronic acid
* Fibrotest
After data collection, all patients will receive blood test for serum hyaluronic acid. If the patients have incomplete laboratory data (except HIV antibody status), they will receive additional blood tests for missing data. All patients will be appointed for transient elastography. All the cost for the extra-investigation will be supported by the study.
Transient elastography (TE or Fibroscan):
TE will be used to evaluate liver fibrosis. TE will be performed in all patients by examiners who were blind to clinical, laboratory data. The right lobe of the liver was targeted through an intercostal space access while the patient was lying in the dorsal decubitus position with the right arm in maximal abduction. With the assistance of TE, a liver portion of at least 6-cm thickness, free of large vessels, was identified for examination. The rate of successful measurements was interpreted by the ratio between the number of those validated and total number of measurements. The results were expressed as a median value of the total measurements in kPa. Patients with ascites were excluded from the study due to the limitation of result interpretation.
Data Handling :
Data of each patient will be collected at the OPD, Division of Hematology and Division of Gastroenterology, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
The study will be started after it is approved by the Ethics Committee ofSiriraj Hospital. Patients' identification number will be stored in a separate log book. Results will be reported at the aggregate level only, and individual-level data will never be released.
Sample Size and Statistical analysis Sample size The primary research question of this study is to assess the prevalence of HCV infection in thalassemia major and thalassemia intermediate patients who received prior blood transfusion. From the previous research conducted by Wanachiwanawin W, et al , we estimate that the prevalence of hepatitis C viral infection in thalassemia patient is 20 percent. The sample size is 246 samples according to the calculation with 95 % confident interval.
Statistical analysis
1. The quantitative data, such as age, will be analyzed by mean and standard deviation or by mode and median (in the data that doesn't have normal distribution). The quantitative data, such as sex, will be analyzed by using percentage and 95% confident interval for the prevalence.
2. In comparison between two groups, the quantitative data, such as liver fibrosis: positive or negative, will be compared by using t-test (normality) or Mann-Whitney U-test (non-normality) and the quantitative data will be analyzed by Chi-square test or Fisher's exact test. If the results show statistically significance (P-value \<0.05) more than one value, the Logistic Regression Analysis will be performed and presented by odds ratio and 95% confidence interval.
