Accuracy of the hypospadias diagnoses and surgical treatment registrations in the Danish National Patient Register

Figures & data

Table 1 Medical record availability according to characteristics among 500 patients diagnosed with hypospadias in the Danish National Patient Register, 1995–2012

	Medical record availability
	Available n=463 (92.6%)	Not available n=37 (7.4%)
Year at first diagnosis, n (%)
1995–1998	131 (28.3)	28 (75.7)
1999–2003	122 (26.4)	4 (10.8)
2004–2008	125 (27.0)	5 (13.5)
2009–2012	85 (18.4)	0 (0.0)
Region of Denmark, n (%)
North	34 (7.3)	0 (0.0)
Central	167 (36.1)	8 (21.6)
Southern	84 (18.1)	8 (21.6)
Sealand	28 (6.1)	2 (5.4)
Capital	150 (32.4)	19 (51.4)
Hospital type, n (%)
University	341 (73.7)	13 (35.1)
Referral	112 (26.3)	24 (64.9)
Department type, n (%)
Pediatric urology or surgery	324 (70.0)	6 (16.2)
Plastic surgery	118 (25.5)	17 (46.0)
General surgery or urology	21 (4.5)	7 (18.9)
Other	0 (0.0)	7 (18.9)
Number of ICD-10 hypospadias diagnoses in DNPR, n (%)
1	53 (11.5)	7 (18.9)
≥2	410 (88.5)	30 (81.1)
Genetic syndromes or other congenital abnormalities,a n (%)
Yes	130 (28.1)	6 (16.2)
No	333 (71.9)	31 (83.8)

Note:

a Genetic syndromes or congenital abnormalities (Q00–Q99) other than hypospadias (Q54, Q540, Q540A, Q541, Q542, Q543, Q548, and Q549).

Abbreviation: DNPR, Danish National Patient Register; ICD, International Classification of Diseases.

Table 2 Positive predictive values of the hypospadias diagnoses among 463 patients in the Danish National Patient Register, 1995–2012

	ICD-10	Accuracy of the first diagnosisa				Accuracy of the most severe diagnosisb
		Sample	Ratioc	PPV (%)	95% CI (%)	Sample	Ratioc	PPV (%)	95% CI (%)
Overall hypospadiasd	Q54d	463	450/463	97.6	95.8–98.7	463	450/463	97.6	95.8–98.7
Glandular or coronal hypospadias	Q540 Q540A	235	152/235	64.7	58.3–70.6	208	150/208	72.1	65.6–77.8
Corporal hypospadias	Q541	92	50/92	54.3	43.9–64.4	173	98/173	56.6	49.1–63.9
Penoscrotal hypospadias	Q542	22	16/22	72.7	49.0–88.1	33	18/33	54.5	36.8–71.2
Perineal hypospadias	Q543	2	1/2	50.0	–	8	3/8	37.5	8.7–79.1
Other or unspecified hypospadiase	Q548 Q549	112	110/112	98.2	93.1–99.6	41	39/41	95.1	82.2–98.8

Notes:

a Accuracy of the first ICD-10 diagnosis of hypospadias registered in the DNPR from 1995 to 2012.

b Accuracy of the most severe ICD-10 diagnosis of hypospadias registered in the DNPR from 1995 to 2012.

c Ratio denotes confirmed diagnoses/available records.

d Overall PPV for all ICD-10 codes for hypospadias, Q54, Q540, Q540A, Q541, Q542, Q543, Q548, and Q549.

e Accuracy of other (Q548) or unspecified hypospadias (Q549) registration in regard to the number of diagnoses that could be confirmed as any form of hypospadias in the medical record review.

Abbreviations: DNPR, Danish National Patient Register; ICD, International Classification of Diseases; PPV, positive predictive value.

Figure 1 Percentage distribution of the ICD-10 diagnoses codes for subtypes of hypospadias registered in the Danish National Patient Register (A) and subtype of hypospadias based on medical record review (B).

Abbreviation: ICD, International Classification of Diseases.

Figure 2 Percentage distribution of the operation codes for surgical treatment of hypospadias registered in the Danish National Patient Register (A) and surgical treatment of hypospadias based on medical record review (B).

Table 3 Positive predictive values of surgical treatment of hypospadias among 329 patients in the Danish National Patient Register, 1995–2012

	ICD-10	Sample	Ratioa	PPV (%)	95% CI (%)
Overall surgical treatment for hypospadiasb	KGH60b	329	328/329	99.7	97.9–99.9
Hypospadias, unspecificc	KGH60	268	267/268	99.6	97.4–99.9
Glandular or coronal hypospadias	KGH60A	23	20/23	87.0	64.2–96.1
Corporal hypospadias	KGH60B	34	28/34	82.4	64.8–92.2
Penoscrotal hypospadias	KGH60C	4	3	75.0	4.1–99.5
Perineal hypospadias	KGH60D	0	–	–	–

Notes:

a Ratio denotes confirmed diagnoses/available records.

b The overall PPV for all surgical treatment codes (KGH60, KGH60A, KGH60B, KGH60C, and KGH60D) for hypospadias among the 329 patients with available descriptions from surgical treatment.

c The PPV for the unspecific hypospadias operation code KGH60, calculated as the number of boys with a hypospadias operation verified in the medical records/number of boys registered with KGH60.

Abbreviations: ICD, International Classification of Diseases; PPV, positive predictive value.

Table 4 Positive predictive values of the hypospadias diagnosis stratified by potentially modifying characteristics among 463 patients in the Danish National Patient Register, 1995–2012

	Overall hypospadias diagnoses
	Ratio	PPV (%)	95% CI (%)
Year at first diagnosis
1995–1998	127/131	96.9	92.1–98.9
1999–2003	117/122	95.9	90.5–98.3
2004–2008	122/125	97.6	92.8–99.2
2009–2012	84/85	98.8	92.0–99.8
Region of Denmark
North	33/34	97.1	81.3–99.6
Central	164/176	98.2	94.5–99.9
Southern	81/84	96.4	89.4–98.9
Sealand	28/28	100.0	–
Capital	144/150	96.0	91.3–98.2
Hospital type
University	336/341	98.5	96.5–99.4
Referral	114/122	93.4	87.4–96.7
Department type
Pediatric urology or surgery	320/324	98.8	96.7–99.5
Plastic surgery	116/118	98.3	93.4–99.6
General surgery or urology	14/21	66.7	44.1–83.6
Number of ICD-10 hypospadias diagnoses in DNPR
1	48/53	90.6	79.1–96.1
≥2	402/410	98.0	96.1–99.0
Response time
Fast	372/382	97.4	95.2–98.6
Slow	78/81	96.4	89.0–98.8
Genetic syndromes or other congenital abnormalitiesb
Yes	126/130	96.9	92.0–98.8
No	224/333	97.3	94.9–98.6

Notes:

a Overall hypospadias diagnoses, any type; Q54, Q540, Q540A, Q541, Q542, Q543, Q548, and Q549.

b Genetic syndromes or congenital abnormalities (Q00–Q99) other than hypospadias (Q54, Q540, Q540A, Q541, Q542, Q543, Q548, and Q549).

Abbreviations: DNPR, Danish National Patient Register; ICD, International Classification of Diseases; PPV, positive predictive value.