Quantitative Vaccine Response
The Log10 titer was used as the quantitative vaccine response.
Unadjusted Relationship of Hepatitis B Vaccine Response (Log10 Titer) and Potential Impact Factors Among Subjects Whose Week 28 Antibody Results Are Within Week 28 Visit Window.
The Log10 titer at Week 28 was used as the quantitative continuous vaccine response.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen (Binary); Predictor: STUDY ARM.
Qualitative Vaccine Response to Hepatitis B Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Study arm was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: SITE EFFECT
Qualitative Vaccine Response to Hepatitis B Surface Antigen is defined as a "Responder" if serum antibody level is >= 10 mIU/mL and a "Non- Responder" if a serum a'body level is < 10 mIU/mL. Site effect was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: AGE
Qualitative Vaccine Response to Hepatitis B (Hep B)Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Age was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: GENDER
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum a'body level is < 10 mIU/mL. Gender was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: HISPANIC ETHNICITY
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Hispanic ethnicity was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: RACE
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Race was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: TANNER STAGE FOR FEMALES
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Tanner stage by gender was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: TANNER STAGE FOR MALES
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Tanner stage by gender was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: BMI at Baseline
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. BMI at baseline was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: EVER SMOKED CIGARETTES
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Whether participants ever smoked cigarettes was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: SEXUAL IDENTITY
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Sexual identity was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: AGE AT WHICH SUBJECT FIRST HAD SEX (NOT FORCED)
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Age of participants' first unforced sexual encounter was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: TOTAL LIFETIME SEX PARTNERS
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Total number of lifetime sex partners was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: TOTAL LIFETIME MALE SEX PARTNERS
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Total number of lifetime male sex partners was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: TOTAL LIFETIME FEMALE SEX PARTNERS
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Total number of lifetime female sex partners was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: EVER DRANK ALCOHOL
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Whether participants ever drank alcohol was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: EVER SMOKED MARIJUANA
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Whether participants ever smoked marijuana was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Outcome Measure: Qualitative Vaccine Response to Hepatitis B Surface Antigen (Binary); Predictor: EVER USED DRUGS NOT PRESCRIBE
Qualitative Vaccine Response to Hepatitis B (Hep B) Surface Antigen is defined as a "Responder" if serum a'body level is >= 10 mIU/mL and a "Non- Responder" if a serum antibody level is < 10 mIU/mL. Whether participants ever used drugs not prescribed was analyzed as a potential impact factor and was measured and examined for the association with both the presence of adequate response as well as the quantitative titer one month post 2 vaccine doses.
Immunogenicity to Hep B 18 Months After First Immunization
Persistence of protective antibody response was measured by presence or absence of 10 mIU/ml HepB surface antibody and geometric mean titer of the same antibody at Week 76
Immunogenicity to Hep A in the Twinrix Arm: One Month Post 2nd Vaccination
Hepatitis A antibody response in those subjects in the combined vaccine arm (Twinrix) at 1 month after the 2nd vaccination. Immunogenicity to Hepatitis is given as a positive or negative response. If the Hepatitis A serology was reactive, then the participant was considered to have a positive response; if the Hepatitis A serology was non-reactive, then the participant was considered to have a negative response.
Immunogenicity to Hep A in Twinrix Arm: Twelve Months Post 2nd Vaccination
Hepatitis A antibody response in those subjects in the combined vaccine arm (Twinrix) at 12 months after the 2nd vaccination. Immunogenicity to Hepatitis is given as a positive or negative response.
Immunogenicity to Hep A in Twinrix Arm: Overall Response (1-month or 12-month After 2nd Vaccination)
Hepatitis A antibody response in those subjects in the combined vaccine arm (Twinrix) at two time points: 1 and 12 months after the 2nd vaccination. Immunogenicity to Hepatitis is given as a positive or negative response.
As Treated Analysis - Adequate Antibody Response to Hep B Surface Antigen
The subject was considered seroresponsive to Hepatitis B Surface Antigen if the serum antibody level was greater than or equal to 10 mIU/mL. Those who received only a single vaccination, whose second vaccination was outside of the specified time window, or other cases of protocol violations were excluded from the analysis.
Assessment of Youth Understanding of Vaccine Trial and Informed Consent
Assessment of understanding was measured by a questionnaire containing six questions. The summary score is the sum of correct answers from six questions.