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A Mixed Effects Model for Gastric Ulcer Data

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Abstract

The concern of this work is the statistical evaluation of healing rate of gastric ulcers. To measure healing progress, the distance of linear advance of a specific ulcer margin toward center is recommended as an appropriate parameter. The sequence of linear advances is approximately linear over time; thus, the slope of this linear profile provides a good indication of the healing rate of the specific ulcer area. To estimate the mean slope in a treatment group, the mixed effects model technique is employed. A treatment effects comparison is made by both the F-test and the likelihood ratio test for a common slope across treatments. Also discussed are the advantages of using the linear advance as an endpoint and the mixed effects model technique as an analysis tool. A numerical example is presented as an illustration.

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References

  1. Poynard T. Pignon U-P. Duodenal ulcer. Analyses of 93 randomized clinical trials. London and Paris: John Libbey Eurotext; 1989.

    Google Scholar 

  2. Pecoraro RE. et al. Chronology and Determinants of Tissue Repair in Diabetic Lower-Extremity Ulcers. Diabetes. 1991;40:1305–1313.

    Article  CAS  Google Scholar 

  3. Gilman TH. Parameter for Measurement of Wound Closure. Wounds. 1990;2(3):May/June 95–101.

    Google Scholar 

  4. Margolis DM, et al. Planimetric rate of healing in venous ulcers of the leg treated with pressure bandage and hydrocolloid dressing. J Am Acad Dermatol. 1993;28(3):418–421.

    Article  CAS  Google Scholar 

  5. Laird NM. Ware JH. Random-effects models for longitudinal data. Biometrics. 1982;38(4):963–974.

    Article  CAS  Google Scholar 

  6. SAS/STAT Software Changes and Enhancements through Release 6.11. Cary, NC: SAS Institute Inc.; 1996.

  7. Advanced General Linear Models with and Emphasis on Mixed Models Course Notes. Cary, NC: SAS Institute Inc.; 1996.

  8. Jennrich RI. Schluchter MD. Unbalanced Repeated-Measures Models with Structured Covariance Matrices. Biometrics. 1986;42;805–820.

    Article  CAS  Google Scholar 

  9. Gornbein JA. Laxaro CG, Little RJA. Incomplete data in repeated measures analysis. Stat methods Med Res. 1992;1:275–295.

    Article  CAS  Google Scholar 

Download references

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Authors and Affiliations

  1. Biometrics Research Department, Merck Research Laboratories, PO Box 2000, RY70-38, Rahway, NJ, 07065-0900, USA

    Donghui Zhang PhD (Biometrician)

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  1. Donghui Zhang PhD
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Zhang, D. A Mixed Effects Model for Gastric Ulcer Data. Ther Innov Regul Sci 31, 1249–1254 (1997). https://doi.org/10.1177/009286159703100425

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  • DOI: https://doi.org/10.1177/009286159703100425

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