I S Chan
Affiliation: Merck Research Laboratories
- Proving non-inferiority or equivalence of two treatments with dichotomous endpoints using exact methodsI S F Chan
Clinical Biostatistics, Merck Research Laboratories, West Point, PA 19486, USA
Stat Methods Med Res 12:37-58. 2003..Finally, we illustrate with several examples the application of these exact methods in analysing and planning non-inferiority or equivalence trials...
- Test-based exact confidence intervals for the difference of two binomial proportionsI S Chan
Clinical Biostatistics, Merck Research Laboratories, West Point, Pennsylvania 19486, USA
Biometrics 55:1202-9. 1999..We show that a large improvement can be achieved by using the standardized Z test with a constrained maximum likelihood estimate of the variance...
- Statistical analysis of noninferiority trials with a rate ratio in small-sample matched-pair designsIvan S F Chan
Clinical Biostatistics, Merck Research Laboratories, UN A102, West Point, Pennsylvania, USA
Biometrics 59:1170-7. 2003..We illustrate these methods using two real examples taken from a crossover study of soft lenses and a Pneumocystis carinii pneumonia study. We contrast the methods with a hypothetical example...
- Power and sample size determination for noninferiority trials using an exact methodIvan S F Chan
Clinical Biostatistics, Merck Research Laboratories, UN A102, PO Box 4, West Point, PA 19486, USA
J Biopharm Stat 12:457-69. 2002..Therefore, it is a very desirable tool for planning noninferiority trials, especially in situations where asymptotic methods are likely to fail...
- Use of statistical models for evaluating antibody response as a correlate of protection against varicellaIvan S F Chan
Clinical Biostatistics, Merck Research Laboratories, Merck and Co, West Point, PA 19486, USA
Stat Med 21:3411-30. 2002..In addition, we explore the potential use of these models to predict long-term disease breakthrough rates and to estimate the predicted vaccine efficacy of a similar varicella vaccine made with a modified manufacturing process...
- Exact tests of equivalence and efficacy with a non-zero lower bound for comparative studiesI S Chan
Merck Research Laboratories, West Point, PA 19486, USA
Stat Med 17:1403-13. 1998..Variances of test statistics are estimated via a constrained maximum likelihood method (Farrington and Manning). Data from oncology and vaccine clinical trials are used to illustrate the exact tests...
- Statistical considerations for noninferiority/equivalence trials in vaccine developmentW W B Wang
Clinical Biostatistics, Merck Research Laboratories, North Wales, Pennsylvania 19454, USA
J Biopharm Stat 16:429-41. 2006....
- Childhood vaccination against varicella: persistence of antibody, duration of protection, and vaccine efficacyS J Vessey
Merck Research Laboratories, Merck and Co, Inc, West Point, Pennsylvania 19482, USA
J Pediatr 139:297-304. 2001..1%). Varicella cases in vaccinated children generally were mild. CONCLUSION: The live attenuated varicella vaccine is highly effective in inducing persistent immunity and long-term protection against breakthrough varicella infection...
- A double-blind, randomized, controlled, multicenter safety and immunogenicity study of a refrigerator-stable formulation of ZostavaxLarry I Gilderman
University Clinical Research, Pembroke Pines, Florida, USA
Clin Vaccine Immunol 15:314-9. 2008..The refrigerator-stable formulation of Zostavax has an acceptable safety profile and is as immunogenic as the frozen formulation; thus, the vaccine may be used in clinical settings where freezer availability is limited...
- Varicella-zoster virus-specific immune responses in elderly recipients of a herpes zoster vaccineM J Levin
University of Colorado Health Sciences Center, Denver, Colorado, USA
J Infect Dis 197:825-35. 2008..The trial included an immunology substudy to determine the relationship of VZV-specific immune responses to vaccination and clinical outcome...
- Immunogenicity of Oka/Merck varicella vaccine in children vaccinated at 12-14 months of age versus 15-23 months of ageJeffrey L Silber
Merck and Co, Inc, West Point, PA 19486, USA
Pediatr Infect Dis J 26:572-6. 2007..An analysis of 5 postlicensure clinical trials with this vaccine was conducted to evaluate immune response relative to the age of the vaccine recipient...
- The impact of acute herpes zoster pain and discomfort on functional status and quality of life in older adultsKenneth E Schmader
Duke University, Durham, NC, USA
Clin J Pain 23:490-6. 2007....
- Detecting qualitative interactions in clinical trials: an extension of range testJianjun Li
Clinical Biostatistics, Merck Research Laboratories, Blue Bell, Pennsylvania, USA
J Biopharm Stat 16:831-41. 2006..It is also illustrated through a real clinical trial example that the extended range test detects the qualitative interaction while the range test and likelihood ratio test do not...
- Safety, tolerability, and immunogenicity of a two-dose regimen of high-titer varicella vaccine in subjects > or =13 years of ageClemente Diaz
University of Puerto Rico School of Medicine, San Juan, Puerto Rico
Vaccine 24:6875-85. 2006..2%, but generally were mild. Immunogenicity were similar in both groups in seronegative subjects. PUVV was generally well tolerated, and elicited an immune response similar to that induced by the marketed formulation of VARIVAX...
- Confidence interval construction for proportion difference in small-sample paired studiesMan Lai Tang
Department of Mathematics, Hong Kong Baptist University, Kowloon Tong, Hong Kong
Stat Med 24:3565-79. 2005..We illustrate the methods using real examples from a pain management study and a cancer study...
- Correlation coefficient inference on censored bioassay dataLiang Li
Department of Biostatistics and Epidemiology, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
J Biopharm Stat 15:501-12. 2005..In addition, the proposed method works with many types of censored data in a similar way. Furthermore, we proposed an Monte Carlo exact test to assess the goodness-of-fit of the model...
- Inverse relationship between six week postvaccination varicella antibody response to vaccine and likelihood of long term breakthrough infectionShu Li
Merck Research Laboratories, Merck and Co, Inc, West Point, PA 19486, USA
Pediatr Infect Dis J 21:337-42. 2002....
- A comparison of safety, tolerability and immunogenicity of Oka/Merck varicella vaccine and VARILRIX in healthy childrenYu Lung Lau
Queen Mary Hospital, Pokfulum, Hong Kong, PR China
Vaccine 20:2942-9. 2002..Safety profiles in each treatment group were similar. The proportions of subjects achieving a 6-week postvaccination titer> or = 5 gpELISA units in Groups A, B or C were 97.1, 95.2 and 85.6%, respectively...
- Measurement of cell-mediated immunity with a Varicella-Zoster Virus-specific interferon-gamma ELISPOT assay: responses in an elderly population receiving a booster immunizationJeffrey G Smith
WP26B 1144, Department of Virus and Cell Biology, Merck and Co, Inc, PO Box 4, West Point, PA 19486, USA
J Med Virol 70:S38-41. 2003..The increase from pre to post booster vaccination response was more pronounced (approximately 2.2-fold rise) in a subset of subjects who had received two prior immunizations with a live, attenuated vaccine...
- A cautionary note on exact unconditional inference for a difference between two independent binomial proportionsDevan V Mehrotra
Merck Research Laboratories, UN A102, 785 Jolly Rd, Bldg C, Blue Bell, Pennsylvania 19422, USA
Biometrics 59:441-50. 2003..Boschloo's test, in which the p-value from Fisher's test is used as the test statistic in an exact unconditional test, is uniformly more powerful than Fisher's test, and is also recommended...
- Decline in varicella-zoster virus (VZV)-specific cell-mediated immunity with increasing age and boosting with a high-dose VZV vaccineMyron J Levin
Department of Pediatrics, Section of Infectious Diseases, University of Colorado School of Medicine, Denver, Colorado, USA
J Infect Dis 188:1336-44. 2003..A live attenuated VZV vaccine is safe and immunogenic in an elderly population, and the vaccine-induced immunity may be monitored by the IFN-gamma ELISPOT assay...
- Development of a measure of the burden of pain due to herpes zoster and postherpetic neuralgia for prevention trials: adaptation of the brief pain inventoryPaul M Coplan
Merck Research Laboratories, West Point, Pennsylvania 19486, USA
J Pain 5:344-56. 2004..These findings support the validity and utility of the ZBPI, the definition of PHN, and the severity-duration measure of the burden of HZ illness...
- Vaccination against Herpes Zoster and Postherpetic NeuralgiaMichael N Oxman
VA San Diego Healthcare System, San Diego, California, USA
J Infect Dis 197:S228-36. 2008..VZV vaccines can boost VZV-CMI. Therefore, we tested the hypothesis that VZV vaccination would protect older adults against HZ and PHN...
- Safety and tolerability of a high-potency zoster vaccine in adults >/= 50 or years of ageStephen K Tyring
University of Texas Health Science Center, Houston, TX, USA
Vaccine 25:1877-83. 2007..This study of people >/= 50 or years of age compared the safety and tolerability of two zoster vaccine potencies...
- Safety and immunogenicity profile of the concomitant administration of ZOSTAVAX and inactivated influenza vaccine in adults aged 50 and olderBoris Kerzner
Health Trends Research, Baltimore, Maryland, USA
J Am Geriatr Soc 55:1499-507. 2007..To evaluate the safety and immunogenicity of ZOSTAVAX administered concomitantly with inactivated influenza vaccine or sequentially in adults aged 50 and older...
- Noninferiority and equivalence trialsIvan S F Chan
J Biopharm Stat 14:261-2. 2004