• 1
    Eifel PJ, Morris M, Wharton JT, Oswald MJ. The influence of tumor size and morphology on the outcome of patients with FIGO stage IB squamous cell carcinoma of the uterine cervix. Int J Radiat Oncol Biol Phys. 1994; 29: 9-16.
  • 2
    Landoni F, Maneo A, Colombo A, et al. Randomised study of radical surgery versus radiotherapy for stage Ib-IIa cervical cancer. Lancet. 1997; 350: 535-540.
  • 3
    Sevin BU, Nadji M, Lampe B, et al. Prognostic factors of early stage cervical cancer treated by radical hysterectomy. Cancer. 1995; 76: 1978-1986.
  • 4
    Soisson AP, Soper JT, Clarke-Pearson DL, Berchuck A, Montana G, Creasman WT. Adjuvant radiotherapy following radical hysterectomy for patients with stage IB and IIA cervical cancer. Gynecol Oncol. 1990; 37: 390-395.
  • 5
    Samlal RA, van der Velden J, Ketting BW, et al. Disease free interval and recurrence pattern after the Okabayashi variant of Wertheim's radical hysterctomy for stage IB and IIA cervical carcinoma. Int J Gynecol Cancer. 1996; 6: 120-127.
  • 6
    Smiley LM, Burke TW, Silva EG, Morris M, Gershenson DM, Wharton JT. Prognostic factors in stage IB squamous cervical cancer patients with low risk for recurrence. Obstet Gynecol. 1991; 77: 271-275.
  • 7
    Keys HM, Bundy BN, Stehman FB, et al. Cisplatin, radiation, and adjuvant hysterectomy compared with radiation and adjuvant hysterectomy for bulky stage IB cervical carcinoma. N Engl J Med. 1999; 340: 1154-1161.
  • 8
    Morris M, Eifel PJ, Lu J, et al. Pelvic radiation with concurrent chemotherapy compared with pelvic and para-aortic radiation for high-risk cervical cancer. N Engl J Med. 1999; 340: 1137-1143.
  • 9
    Peters WA III, Liu PY, Barrett RJ, et al. Concurrent chemotherapy and pelvic radiation therapy compared with pelvic radiation therapy alone as adjuvant therapy after radical surgery in high-risk early-stage cancer of the cervix. J Clin Oncol. 2000; 18: 1606-1613.
  • 10
    Rotman M, Sedlis A, Piedmonte MR, et al. A phase III randomized trial of postoperative pelvic irradiation in stage IB cervical carcinoma with poor prognostic features: follow-up of a gynecologic oncology group study. Int J Radiat Oncol Biol Phys. 2006; 65: 169-176.
  • 11
    Sedlis A, Bundy BN, Rotman MZ, Lentz SS, Muderspach LI, Zaino RJ. A randomized trial of pelvic radiation therapy versus no further therapy in selected patients with stage IB carcinoma of the cervix after radical hysterectomy and pelvic lymphadenectomy: a Gynecologic Oncology Group Study. Gynecol Oncol. 1999; 73: 177-183.
  • 12
    Grigsby PW. Cervical cancer: combined modality therapy. Cancer J. 2001; 7( suppl 1): S47-S50.
  • 13
    van der Velden J, Samlal R, Schilthuis MS, Gonzalez DG, ten Kate FJ, Lammes FB. A limited role for adjuvant radiotherapy after the Wertheim/Okabayashi radical hysterectomy for cervical cancer confined to the cervix. Gynecol Oncol. 1999; 75: 233-237.
  • 14
    Rotman M, Sedlis A, Piedmonte MR, et al. A phase III randomized trial of postoperative pelvic irradiation in stage IB cervical carcinoma with poor prognostic features: follow-up of a gynecologic oncology group study. Int J Radiat Oncol Biol Phys. 2006; 65: 169-176.
  • 15
    Biewenga P, van der Velden J, Mol BW, et al. Validation of existing prognostic models in patients with early-stage cervical cancer. Gynecol Oncol. 2009; 115: 277-284.
  • 16
    Delgado G, Bundy B, Zaino R, Sevin BU, Creasman WT, Major F. Prospective surgical-pathological study of disease-free interval in patients with stage IB squamous cell carcinoma of the cervix: a Gynecologic Oncology Group study. Gynecol Oncol. 1990; 38: 352-357.
  • 17
    Sevin BU, Lu Y, Bloch DA, Nadji M, Koechli OR, Averette HE. Surgically defined prognostic parameters in patients with early cervical carcinoma. A multivariate survival tree analysis. Cancer. 1996; 78: 1438-1446.
  • 18
    Little RJ, Rubin DB. Causal effects in clinical and epidemiological studies via potential outcomes: concepts and analytical approaches. Annu Rev Public Health. 2000; 21: 121-145.
  • 19
    Schafer JL. Analysis of Incomplete Multivariate Data. London, UK: Chapman & Hall; 1997.
  • 20
    Moons KG, Donders RA, Stijnen T, Harrell FE Jr. Using the outcome for imputation of missing predictor values was preferred. J Clin Epidemiol. 2006; 59: 1092-1101.
  • 21
    Harrell FE.TheHmisclibrary.Available at: 2008 Accessed on…
  • 22
    Schafer JL, Graham JW. Missing data: our view of the state of the art. Psychol Methods. 2002; 7: 147-177.
  • 23
    Harrell FE Jr, Lee KL, Pollock BG. Regression models in clinical studies: determining relationships between predictors and response. J Natl Cancer Inst. 1988; 80: 1198-1202.
  • 24
    Kaplan EL, Meier P. Nonparametric estimation from incomplete observations. J Am Stat Assoc. 1958; 53: 457-481.
  • 25
    Cox DR. Regression models and life-tables. J R Stat Soc. 1972; 34: 187-220.
  • 26
    Harrell FE. Regression Modeling Strategies: With Applications to Linear Models, Logistic Regression, and Survival Analysis. New York, NY: Springer; 2001.
  • 27
    Steyerberg EW, Eijkemans MJ, Habbema JD. Stepwise selection in small data sets: a simulation study of bias in logistic regression analysis. J Clin Epidemiol. 1999; 52: 935-942.
  • 28
    Steyerberg EW. Clincial Prediction Models. A Practical Approach to Development, Validation, and Updating. New York, NY: Springer; 2009.
  • 29
    Steyerberg EW, Bleeker SE, Moll HA, Grobbee DE, Moons KG. Internal and external validation of predictive models: a simulation study of bias and precision in small samples. J Clin Epidemiol. 2003; 56: 441-447.
  • 30
    Van Houwelingen JC, Le CS. Predictive value of statistical models. Stat Med. 1990; 9: 1303-1325.
  • 31
    Heagerty PJ, Lumley T, Pepe MS. Time-dependent ROC curves for censored survival data and a diagnostic marker. Biometrics. 2000; 56: 337-344.
  • 32
    Bleeker SE, Moll HA, Steyerberg EW, et al. External validation is necessary in prediction research: a clinical example. J Clin Epidemiol. 2003; 56: 826-832.
  • 33
    Stolwijk AM, Zielhuis GA, Hamilton CJ, et al. Prognostic models for the probability of achieving an ongoing pregnancy after in-vitro fertilization and the importance of testing their predictive value. Hum Reprod. 1996; 11: 2298-2303.
  • 34
    Wasson JH, Sox HC, Neff RK, Goldman L. Clinical prediction rules. Applications and methodological standards. N Engl J Med. 1985; 313: 793-799.
  • 35
    Monk BJ, Wang J, Im S, et al. Rethinking the use of radiation and chemotherapy after radical hysterectomy: a clinical-pathologic analysis of a Gynecologic Oncology Group/Southwest Oncology Group/Radiation Therapy Oncology Group trial. Gynecol Oncol. 2005; 96: 721-728.