Table 3.

Clinical associations also found in the ‘Original’ Medline 1000 dataset

ICD-9 code	Description	ICD-9 code	Description	Association p value derived from Clinical dataset	Clinically surprising?	Number of Medline citations with both concepts mentioned	Supporting citations (PMID)†	Citation could be interpreted as describing an association?
1st percentile (highest ranked associations)
290.0	Senile dementia	331.0	Alzheimer's disease	<5×10−324	No	1139	11138345 2614500 7056516	No Yes No
344.61	Cauda equina syndrome with neurogenic bladder	596.54	Neurogenic bladder	<5×10−324	No	11	11880062 16813905 3400548	* No No
184.4	Malignant neoplasm of vulva	233.3	Carcinoma in situ, unspecified female genital organs	<5×10−324	No	1	2082867	*
396.2	Mitral valve insufficiency and aortic valve stenosis	424.1	Aortic valve disorders	<5×10−324	No	2	11163732 9665226	Yes Yes
362.21	Retrolental fibroplasia	769	Respiratory distress syndrome in newborn	<5×10−324	No	92	12709796 19568962 15716610	* * *
25th percentile
268.9	Unspecified vitamin D deficiency (268.9)	782.2	Localized superficial swelling, mass, or lump	3.8×10−68	Yes	3	11233710 21806909 9339283	No No No
558.1	Gastroenteritis and colitis due to radiation	789.0	Abdominal pain	7.1×10−68	No	1	8140765	Yes
279.5	Graft-versus-host disease	E888.9	Accidental fall	2.4×10−67	Yes‡	1	9250172	No
131.9	Trichomoniasis	590.80	Pyelonephritis	3.0×10−67	*	1	9286064	*
078.19	Viral warts	622.11	Mild dysplasia of cervix	8.4×10−67	No	1	7559948	Yes
50th percentile
276.52	Hypovolemia	403.9	Hypertensive renal disease	9.8×10−23	No	73	11602456 17113396 365408	Yes Yes No
255.41	Glucocorticoid deficiency	788.3	Functional urinary incontinence	4.8×10−22	Yes	1	9836036	Yes
413.9	Angina pectoris	596.51	Hypertonicity of bladder	7.0×10−22	Yes	1	17689623	No
286.9	Coagulation defect	344.00	Quadriplegia	8.0×10−22	*	4	11403538 16958632 3508705	No Yes No
229.9	Benign neoplasm of unspecified site	354.0	Carpal tunnel syndrome	4.9×10−21	Yes	1	1672719	*
75th percentile
416.9	Chronic pulmonary heart disease	783.41	Failure to thrive	4.6×10−6	No	24	12597677 8165079 2657582	Yes Yes Yes
351.0	Bell's palsy	742.59	Congenital anomalies of spinal cord	4.7×10−6	No	1	18756840	No
302.72	Psychosexual dysfunction with inhibited sexual excitement	576.2	Obstruction of bile duct	4.6×10−6	Yes	1	16402030	No
259.9	Endocrine disorder	368.00	Amblyopia	4.6×10−6	Yes	1	15105955	Yes
611.72	Lump or mass in breast	759.6	Hamartoses	4.7×10−6	No	1	19737912	*
100th percentile (lowest ranked associations)
571.2	Alcoholic cirrhosis of liver	617.9	Endometriosis	0.99	Yes	1	8834254	*
153.9	Malignant neoplasm of colon	487.1	Influenza with other respiratory manifestations	0.99	Yes	3	12889684 18544745 20813181	No No No
454.0	Varicose veins of lower extremities with ulcer	691.8	Other atopic dermatitis and related conditions	0.98	Yes	1	3442079	No
585.6	End stage renal disease	626.0	Absence of menstruation	0.99	No	23	3130865 16619340 9593608	Yes * Yes
110.5	Dermatophytosis of the body	135	Sarcoidosis	0.99	Yes	1	11476274	No

These were selected from the area of overlap in figure 3A. The lower-ranked associations tend to be more clinically surprising. Many of the citations found in the literature did not actually suggest a true association after manual review. Whether an association was clinically surprising was independently determined by two physicians (κ statistic 0.84; 95% CI 0.63 to 1.05). The κ statistic for agreement on whether the citations found by our approach supported the association was 0.55 (95% CI 0.30 to 0.79).

*Opinions for which the physicians differed.

†For associations with more than three citations, three were randomly selected for this analysis.

‡The abstract stated, ‘donor stem cells become tolerant to host antigens and fall to cause GVHD’. The word ‘fall’ was coded into the ICD-9 code for a fall. Not only was this the wrong context for a fall, but the word ‘fall’ in this abstract is actually a typographic error and should have been ‘fail’.

ICD-9, International Classification of Disease, V.9; GVHD, graft-versus-host disease; PMID, PubMed Identifier.