Table 1. Descriptive characteristics of colorectal cancer cases and controls, Kaiser Permanente, Northern California, 1997–2011.

	Cases		Controls
	N/Mean	%/SD	N/Mean	%/SD
Number of participants	12,505		599,534
Ever oral bisphosphonates (>1 yr)	563	4.50%	32,897	5.49%
Ever use oral alendronate (>1 yr)	556	4.45%	32,281	5.38%
Ever use oral etidronate (>1 yr)	13	0.10%	785	0.13%
Ever use oral ibandronate (>1 yr)	4	0.03%	206	0.03%
Ever use oral risedronate (>1 yr)	14	0.11%	989	0.16%
Ever use oral tiludronate (>1 yr)	0	0.00%	4	0.00%
Defined Daily Dose
Never	11,942	95.50%	566,637	94.51%
<12 months	224	1.79%	11,928	1.99%
> = 12 months	339	2.71%	20,969	3.50%
Age at index	66.40	13.00	65.94	12.90
Female	6,027	48.20%	290,996	48.54%
Race/ethnicity
Non-Hispanic white	7,519	60.13%	373,257	62.26%
Non-Hispanic black	1,139	9.11%	51,400	8.57%
Hispanic	1,629	13.03%	75,522	12.60%
Other	2,162	17.29%	97,087	16.19%
Missing	56	0.45%	2,268	0.38%
Smoked tobacco (% yes)	5,013	40.09%	214,862	35.84%
Consumed alcohol (% yes)	3,097	24.77%	131,538	21.94%
Body mass index
Missing	6,286	50.27%	291,630	48.64%
Underweight	17	0.14%	665	0.11%
Normal weight	2,038	16.30%	108,945	18.17%
Overweight	1,859	14.87%	96,253	16.05%
Obese	2,305	18.43%	102,041	17.02%
Charlson comorbidity index	0.85	1.97	0.18	0.79
History of osteoporosis (>1 yr)	5,986	47.87%	308,108	51.39%
Previous lower endoscopy	6,492	51.92%	271,688	45.32%
Previous lower endoscopy (>1 yr)	3,492	27.92%	248,160	41.39%
Previous upper endoscopy (>1 yr)	525	4.20%	37,182	6.20%
Ever use HRT (>1 yr)	2,602	20.81%	146,633	24.46%
Ever use NSAIDs (>1 yr)	8,264	66.09%	427,351	71.28%

Note: >1 yr indicates that the exposure occurred at least one year prior to the index date.