A Non-Parametric Plan

Identify Independent and Dependent Variables with Specific Level of Measurement

Characteristics of 841 triple-negative breast cancer (TNBC) patients. Independent variables; mean age of TNBC patients was 55.8 (SD 13.5); 46.5% of patients had a diagnosis before age 50. Dependent variables; 275 (33.3%) had a progression of the disease (re-occurrence of cancer, metastasis, or death) and 170 (20.2%) died after a mean follow up of 4.3 years (standard deviation, SD, 3.7). Five-year overall survival (OS) and disease-free survival (DFS) were 75.0% and 63.6%.Overall, 25.1% of TNBCs were stage I, 42.7% stage II, 19.1% stage III, and 1.2% stage IV.52.0% of women had a quadrantectomy and 37.9% had a mastectomy; of those who received a quadrantectomy, 94.1% received radiotherapy, while of those who had a mastectomy, 7.5 received radiotherapy; finally, 4.0% of women had neoadjuvant chemotherapy only, 64.8% adjuvant chemotherapy only, and 8.7% received both treatments.

(years) Menopausal statusHistologic grade

<4519022.6 Pre-menopause25530.31111.3

45-5420123.9 Post-menopause50159.6216920.1

55-6422626.9Missing 8510.1360071.3

6522426.6 4617.3

Type of surgeryRadiotherapyChemotherapy

No surgery60.7No00.00Neoadjuvant only 34.04.0

Quadrantectomy 43752.0Yes41194.1Adjuvant only54564.8

Mastectomy31937.9Missing265.9Neoadjuvant and adjuvant738.7

Missing799.4Missing18922.5

Post-mastectomy radiotherapyChemotherapy

No23674.0344.0

Yes247.5

Missing5918.5

Mean age of TNBC patients was 55.8 (SD 13.5); 46.5% of patients had a diagnosis before age 50

1. state the null hypothesis
2. state the research hypothesis
3. state the statistical analysis with rationale