Table 2

Difference in costs and effects of 3-monthly compared with 6-monthly screening for CT and NG infection in MSM at risk of an STI in the Netherlands over 10 years

	Total	CT			NG
	Total	Total	Urethral	Rectal	Total	Urethral	Rectal
Total population
Averted infections	18 249	11 550	7465	4085	6699	2596	4104
Symptomatic	16 033	10 642	7084	3558	5392	2487	2905
Asymptomatic	2215	908	382	527	1307	108	1199
Diagnosed asymptomatic infections*	−24	33	72	−38	−57	12	−71
QALY gained by averting infections	92.1	61.1	40.9	20.2	31.0	14.4	16.5
Costs saved by averting infections (million €)	7.2	4.7	3.0	1.7	2.4	1.1	1.3
Costs made for more frequent screening (million €)	46.8
Population on PrEP
Averted infections	4032	2545	1629	916	1487	571	916
Symptomatic	3539	2343	2545	798	1196	547	649
Asymptomatic	493	201	83	118	291	24	268
Diagnosed asymptomatic infections*	−24	33	72	−38	−57	12	−71
QALY gained by averting infections	20.3	13.4	8.9	4.5	6.9	3.2	3.7
Costs saved by averting infections (million €)	1.6	1.0	0.7	0.4	0.5	0.2	0.3
Costs made for more frequent screening (million €)	46.8
Population not on PrEP
Averted infections	14 218	9005	5837	3169	5212	2025	3188
Symptomatic	12 495	8298	5538	2760	4197	1940	2256
Asymptomatic	1723	707	298	409	1016	84	931
Diagnosed asymptomatic infections*	0	0	0	0	0	0	0
QALY gained by averting infections	71.7	47.6	32.0	15.7	24.1	11.3	12.8
Costs saved by averting infections (million €)	5.6	3.7	2.3	1.4	1.9	0.9	1.0
Costs made for more frequent screening (million €)	0

*It is assumed that asymptomatic infections were only diagnosed at screening visits and thereby treated. Negative numbers indicate more infections being diagnosed and treated at the visits of 6-monthly screening after 10 years.
CT, Chlamydia trachomatis; MSM, men who have sex with men; NG, Neisseria gonorrhoeae; PrEP, pre-exposure prophylaxis; QALY, quality-adjusted life-year.