● ResFlow · Methodology & references

Methodology & references

Every statistical engine in ResFlow is based on open, traceable standard methods. This page collects the methods and key references behind each tool, so you can cite them directly when writing methods or replying to reviewers, and check that the implementation is on track. Each row links to the matching online tool.

How to use this page

① When writing your methods, find the method and reference for each analysis you used and cite it properly; ② to check a tool's implementation, use each tool's "Export R code / R cross-check" to re-run and compare in R (see User guide · validation & cross-check). Use the original articles for the definitive version and page numbers.

Regression & prediction modelling

MethodKey referenceTool
Logistic regressionHosmer DW, Lemeshow S. Applied Logistic Regression. Wiley.Logistic regression
Restricted cubic splines (RCS)Harrell FE. Regression Modeling Strategies, 2nd ed., Springer 2015; Durrleman S, Simon R. Stat Med 1989.RCS splines
NomogramIasonos A, et al. J Clin Oncol 2008;26:1364.Nomogram
Multicollinearity (VIF)Marquardt DW. Technometrics 1970; standard regression diagnostics.Project workbench · diagnostics
Multiple linear regression (OLS, continuous outcome)Standard least squares; Draper NR, Smith H. Applied Regression Analysis, 3rd ed., Wiley 1998.Project workbench · linear regression
Nested model comparison (likelihood-ratio test / AIC)Akaike H. IEEE Trans Automat Contr 1974;19:716; likelihood-ratio test for nested models.Project workbench · model comparison

Survival analysis & competing risks

MethodKey referenceTool
Cox proportional-hazards modelCox DR. JRSS-B 1972;34:187; ties via Breslow NE. Biometrics 1974.Cox regression
Proportional-hazards (PH) testSchoenfeld D. Biometrika 1982; Grambsch PM, Therneau TM. Biometrika 1994;81:515.Project workbench · diagnostics
Harrell C-index (concordance)Harrell FE, et al. Stat Med 1996;15:361.Cox regression
Time-dependent ROC / AUC (IPCW)Uno H, et al. JASA 2007;102:527; Blanche P, et al. Stat Med 2013 (timeROC).Project workbench · time-dependent AUC
Fine-Gray competing risks (subdistribution hazard)Fine JP, Gray RJ. JASA 1999;94:496.Fine-Gray regression
Cumulative incidence function CIF (Aalen-Johansen)Aalen OO, Johansen S. Scand J Stat 1978;5:141.Competing risks CIF
Restricted mean survival time (RMST)Royston P, Parmar MKB. BMC Med Res Methodol 2013;13:152.RMST
Kaplan-Meier survival estimateKaplan EL, Meier P. JASA 1958;53:457.Project workbench · KM curves
Log-rank test (between-group survival)Mantel N. Cancer Chemother Rep 1966;50:163; Peto R, Peto J. JRSS-A 1972;135:185.Project workbench · log-rank

Diagnostic tests & discrimination

MethodKey referenceTool
ROC curve & AUCHanley JA, McNeil BJ. Radiology 1982;143:29.ROC curve
Comparing two ROC curves (DeLong test)DeLong ER, et al. Biometrics 1988;44:837.DeLong test
Calibration & goodness-of-fit (Hosmer-Lemeshow)Hosmer DW, Lemeshow S. Commun Stat 1980;9:1043.Calibration curve
Decision curve analysis (DCA)Vickers AJ, Elkin EB. Med Decis Making 2006;26:565.Decision curve
Likelihood ratios & post-test probability (Fagan nomogram)Fagan TJ. N Engl J Med 1975;293:257.Fagan nomogram
NRI / IDI (reclassification improvement)Pencina MJ, et al. Stat Med 2008;27:157.NRI / IDI

Model validation & calibration

MethodKey referenceTool
Bootstrap internal validation (optimism correction)Harrell FE, et al. Stat Med 1996;15:361; Steyerberg EW, et al. J Clin Epidemiol 2001;54:774; Efron B, Tibshirani R. An Introduction to the Bootstrap, 1993.Project workbench · internal validation
External validation (discrimination & calibration)Steyerberg EW, Vergouwe Y. Eur Heart J 2014;35:1925; Collins GS, et al. Ann Intern Med 2015;162:55.Project workbench · external validation
Calibration slope & calibration curveVan Calster B, et al. J Clin Epidemiol 2016;74:167; Crowson CS, et al. Stat Methods Med Res 2018;27:1885.Project workbench · calibration
Events per variable (EPV)Peduzzi P, et al. J Clin Epidemiol 1996;49:1373 (Logistic); Vittinghoff E, McCulloch CE. Am J Epidemiol 2007;165:710 (Cox).Project workbench · internal validation

Agreement & reliability

MethodKey referenceTool
Bland-Altman agreementBland JM, Altman DG. Lancet 1986;1:307.Bland-Altman
Intraclass correlation coefficient (ICC)Shrout PE, Fleiss JL. Psychol Bull 1979;86:420.ICC
Kappa agreement (two / multiple raters)Cohen J. Educ Psychol Meas 1960; Fleiss JL. Psychol Bull 1971.Kappa

Evidence synthesis & causal

MethodKey referenceTool
Meta-analysis (random effects)DerSimonian R, Laird N. Control Clin Trials 1986;7:177.Meta-analysis
Publication bias (Egger test / funnel plot)Egger M, et al. BMJ 1997;315:629.Funnel plot
Propensity score (PSM / IPTW / SMD)Rosenbaum PR, Rubin DB. Biometrika 1983;70:41; Austin PC. Stat Med 2009.Propensity score
Trend test (Cochran-Armitage)Cochran WG. Biometrics 1954; Armitage P. Biometrics 1955.Trend test

Reporting standards

MethodKey referenceTool
Prediction-model reporting (TRIPOD)Collins GS, et al. Ann Intern Med 2015;162:55.Project workbench · manuscript material
Observational-study reporting (STROBE)von Elm E, et al. Lancet 2007;370:1453.
Randomised-trial reporting (CONSORT)Schulz KF, et al. BMJ 2010;340:c332.
These are the main primary sources for each method, for proper citation and traceability; use the original articles for exact volume/issue/pages and the latest version. The numerical implementations are self-checked (e.g. by reducing to known methods — see User guide · validation & cross-check), but internal performance is optimistic, so key conclusions should be cross-checked against external data and independent implementations such as R before reporting.