Medical Record Review to Differentiate between Idiopathic Parkinson’s Disease and Parkinsonism: A Danish Record Linkage Study with 10 Years of Follow-Up

Table 4

Diagnostic validity of clinical features reported in medical records within 1 year of diagnosis for 2,068 IPD and 378 non-IPD cases.

Criteria	IPD (,068)		Non-IPD ()		value	Sensitivity	Specificity	Positive predictive value	Negative predictive value
		%		%
Symptoms
Tremor	1395	67.5	221	58.5	0.0008	0.67	0.42	0.86	0.19
Rigidity	1352	65.4	221	58.5	0.0080	0.65	0.42	0.86	0.18
Bradykinesia	1311	63.4	206	54.5	0.0009	0.63	0.46	0.86	0.19
Postural instability	236	11.4	118	31.2	<0.0001	0.11	0.69	0.67	0.12
Asymmetrical onset	1761	85.2	226	59.8	<0.0001	0.85	0.40	0.89	0.33
Dementia	38	1.8	53	14.0	<0.0001	0.02	0.86	0.42	0.14
Severe autonomic dysfunction	48	2.3	42	11.1	<0.0001	0.02	0.89	0.53	0.14
Falls	36	1.7	59	15.6	<0.0001	0.02	0.84	0.38	0.14
Fast time to progression	8	0.4	27	7.1	<0.0001	0.00	0.93	0.23	0.15
Sudden symptoms	104	5.0	68	18.0	<0.0001	0.05	0.82	0.60	0.14
Hallucinations unrelated to medication	1	0.0	20	5.3	<0.0001	0.00	0.95	0.05	0.15
Freezing phenomena	18	0.9	8	2.1	0.0299	0.01	0.98	0.69	0.15
Babinski’s sign	41	2.0	28	7.4	<0.0001	0.02	0.93	0.59	0.15
Supranuclear gaze palsy	7	0.3	13	3.4	<0.0001	0.00	0.97	0.35	0.15
Medications used
Levodopa	1027	49.7	213	56.3	0.0108	0.50	0.44	0.83	0.14
Agonist ergoline	309	14.9	33	8.7	0.0009	0.15	0.91	0.90	0.16
Agonist nonergoline	664	32.1	71	18.8	<0.0001	0.32	0.81	0.90	0.18
Amantadine	27	1.3	15	4.0	0.0003	0.01	0.96	0.64	0.15
COMT inhibitor	240	11.6	35	9.3	0.1576	0.12	0.91	0.87	0.16
MAO-B	336	16.2	23	6.1	<0.0001	0.16	0.94	0.94	0.17
Multiple criteria
Conventional criteria (at least 2 of T, R, and B)	1713	82.8	261	69.0	<0.0001	0.83	0.31	0.87	0.25
All 3 cardinal features (T, R, and B)	1360	65.8	161	42.6	<0.0001	0.66	0.57	0.89	0.23
Asymmetrical onset and atypical features	1836	88.8	309	81.7	<0.0001	0.89	0.18	0.86	0.23

Missing onset dates: tremor (3); rigidity (6); bradykinesia (4); postural instability (2); asymmetry (4); first L-dopa treatment (44); first ergoline agonist treatment (91); first nonergoline agonist treatment (65); first amantadine treatment (11); first COMT inhibitor treatment (42); first MAO-B inhibitor treatment (344).
test comparing the proportion of cases with iPD having the clinical features.
T = tremor; R = rigidity; B = bradykinesia.
Atypical features included dementia, early falls, severe symptomatic dysautonomia, fast time to progression, sudden symptoms, hallucination unrelated to medications, freezing phenomena, Babinski’s sign, and supranuclear gaze palsy.