Formally, where S i* (t) is the cumulative expected survival probability for a reference subject of similar sex, age, etc. as the cancer patient and exp (υ i (t)) is the relative survival rate (RSR) at time t.
After all exclusions, 378 Yucheng and 370 matched reference subjects remained for analysis within the current study.
The mean total serum oestradiol level was found to be significantly increased in 8 patients with carcinoma of the breast when compared with 8 healthy reference subjects matched for race, sex and age.
Parameters for which specific data were not available were calibrated to reproduce phenotypes and measurements for a reference subject corresponding to a typical or average healthy subject.
The instantaneous probability of undergoing surgery at time t, given that a patient has not been operated yet, was expressed as: (1) h t, x = h 0 t exp ∑ j β j x j j = 1, 2, …, n where h 0 t is the hazard rate at time t for a reference subject and β j is the log hazard ratio associated with covariate j.
Among the 668 subjects aged <30 years, there were 90 with a matched reference subject who could be successfully followed for a separate analysis.
Although the autocorrelation coefficients for P1 increased from TD1 to TD3 in patients with THA, the autocorrelation coefficients for P1 on all test days and at both walking speeds were significantly lower in patients with THA than in the reference subjects (P ≤0.036 for all).
RESULTS The diabetes risk to members of the Yucheng cohort relative to their reference subjects was significantly increased for women (odds ratio [OR] 2.1 [95% CI 1.1 4.5]) but not for men after considering age, BMI, cigarette smoking, and alcohol intake.
For each breast cancer patient, three reference subjects, who had not undergone surgery for breast cancer, were selected as controls.
For each study cohort patient, 4 reference subjects were identified randomly and matched for gender, age (birth of year), and the year of index ambulatory care visit.
Table 1 also shows the data for the reference subjects aged 20 29 years.
