Table 4.
Matched Cohorts
| Robot | Nonrobot | P Value | |
|---|---|---|---|
| Total n | 533 | 533 | |
| Age [mean (SD)] | 61.09 (14.19) | 61.2 (13.95) | .903 |
| 18–40 y | 7.88 | 8.63 | .943 |
| 41–50 y | 15.57 | 14.07 | |
| 51–60 y | 22.14 | 22.70 | |
| 61–70 y | 26.45 | 27.77 | |
| 71–80 y | 19.51 | 19.51 | |
| >80 y | 8.44 | 7.32 | |
| Gender | |||
| Female | 53.85 | 54.22 | .902 |
| Male | 46.15 | 45.78 | |
| Insurance type | |||
| Government | 48.41 | 49.16 | .574 |
| Managed care | 41.28 | 42.40 | |
| Other | 10.32 | 8.44 | |
| Race | |||
| White | 68.29 | 66.42 | .861 |
| African American | 7.32 | 7.50 | |
| Hispanic | 11.82 | 13.51 | |
| Other | 12.57 | 12.57 | |
| Health status | |||
| APR-DRGa severity level 1 or 2 | 85.18 | 87.43 | .285 |
| APR-DRG severity level 3 or 4 | 14.82 | 12.57 | |
| Region | |||
| Northeast | 30.96 | 27.02 | .400 |
| West | 9.19 | 8.07 | |
| South | 54.78 | 59.66 | |
| Midwest | 5.07 | 5.25 | |
| Location | |||
| Urban | 98.69 | 96.44 | .017 |
| Nonurban | 1.31 | 3.56 | |
| Facility type | |||
| Teaching | 63.60 | 62.66 | .751 |
| Nonteaching | 36.40 | 37.34 | |
| Comorbid conditions | |||
| Arthritis | |||
| Rheumatoid arthritis | 1.69 | 1.13 | .435 |
| Psoriatic arthritis | 0.00 | 0.75 | .157 |
| Ankylosing spondylitis | 0.38 | 0.00 | .045 |
| Malignant neoplasms | |||
| Skin cancer | 0.00 | 0.00 | NA |
| Colon cancer | 12.57 | 12.95 | .854 |
| Lung, bronchus, or trachea | 0.19 | 0.38 | .563 |
| Diseases of digestive system | |||
| GERDa | 12.57 | 13.13 | .784 |
| Gastritis | 5.25 | 6.00 | .595 |
| Gastric ulcer | 0.56 | 0.94 | .478 |
| Crohn disease | 1.13 | 1.31 | .780 |
| Ulcerative colitis | 0.56 | 0.38 | .654 |
| Diverticulitis of colon | 24.58 | 23.26 | .615 |
| Disease of genitourinary system | |||
| Kidney stones | 2.25 | 0.94 | .087 |
| Cystitis | 1.31 | 0.75 | .363 |
| Mental disorders | |||
| Depressive disorders | 6.94 | 6.57 | .807 |
| Neurotic disorders | 4.32 | 4.32 | <.999 |
| Diseases of circulatory system | |||
| Coronary artery disease | 11.44 | 9.94 | .428 |
| Heart failure | 3.56 | 4.32 | .529 |
| MIa (any) | 3.56 | 3.19 | .735 |
| Stroke | 0.75 | 0.94 | .738 |
| Cardiac dysrhythmias | 8.82 | 9.94 | .529 |
| Hypertension | 31.71 | 33.02 | .647 |
| Diseases of musculoskeletal system and connective tissue | |||
| Irritable bowel syndrome | 1.50 | 2.06 | .487 |
| Lumbar disk disease | 1.50 | 2.81 | .140 |
| Osteoporosis | 4.69 | 2.81 | .107 |
| Osteoarthritis | 6.75 | 7.88 | .480 |
| Diseases of nervous system | |||
| Parkinson disease | 0.00 | 0.75 | .045 |
| Multiple sclerosis | 0.38 | 0.00 | .157 |
| Migraine | 2.06 | 1.69 | .652 |
| Diseases of respiratory system | |||
| Chronic bronchitis | 0.94 | 1.69 | .282 |
| Emphysema | 0.38 | 1.31 | .094 |
| Asthma | 5.63 | 6.00 | .794 |
| COPDa | 4.88 | 5.63 | .583 |
| Diseases of skin | |||
| Eczema (dermatitis) | 0.56 | 0.00 | .083 |
| Sebaceous gland diseases | 0.19 | 0.19 | <.999 |
| Metabolic diseases | |||
| Diabetes | 13.51 | 11.07 | .225 |
| Hyperlipidemia | 20.26 | 19.70 | .818 |
| Hypothyroidism | 7.88 | 7.32 | .729 |
| Primary ICD-9 procedure code | |||
| 17.32: laparoscopic cecectomy | 2.06 | 2.06 | <.999 |
| 17.33: laparoscopic right hemicolectomy | 36.77 | 36.77 | |
| 17.35: laparoscopic left hemicolectomy | 7.69 | 7.69 | |
| 17.36: laparoscopic sigmoidectomy | 53.47 | 53.47 | |
| Cancer diagnosis | |||
| Cancer | 30.77 | 27.58 | .284 |
| Non-cancer | 53.66 | 55.91 |
a
APR-DRG = All Patient Refined Diagnosis Related Groups; COPD = chronic obstructive pulmonary disease; GERD = gastroesophageal reflux disease; MI = myocardial infarction; NA = Not Applicable.