Table 2 Incidence, case finding methods and diagnostic criteria of subarachnoid haemorrhage in newly identified studies describing study populations with limited age categories*
Study populationRegionMidyear of studyNo of patient yearsNo of SAH patientsIncidence per 100 000 person years (95% CI)Additional case finding methods‡% of patients with CTAdditional diagnostic criteria††Restriction of study population: age (y)
Oyabe28Japan1984492 88512425.2 (20.7 to 29.6)abj‡‡‡‡>25
Novosibirsk34Russia1987971 751646.6 (5.0 to 8.2)aehjm**AB25–74
Turku15Finland19871 249 99227822.2 (19.6 to 24.9)abeam‡‡AB>25
FINMONICA†16Finland19883 863 08895624.7 (23.2 to 26.3)aeh84§ABC25–74
FINSTROKE14Finland19931 933 66036018.6 (16.7 to 20.5)aehk86AB25–74
Arcadia19Greece1994161 548148.7 (4.1 to 13.2)abeh82AB>20
Manhattan38USA1994428 775399.1 (6.2 to 12.0)befikl99¶AC>20
Innhered32Norway199569 2951318.8 (8.6 to 29.0)abdegk88BD>15
ACROSS†6Australia, N Zealand19974 916 1544008.1 (7.3 to 8.9)aefk90§ABC>15
  • SAH, subarachnoid haemorrhage.

  • *Studies listed in ascending order of midyear of data collection and are additional to those in the previous review.

  • †Studies based primarily on SAH, in contrast with general stroke studies.

  • ‡Case finding methods. For inclusion, involvement of all hospitals in the region necessary and at least a or b. a = death certificates; b = general practitioners; c = rehabilitation; d = nursing homes; e = regular search; f = review radiology requests; g = media attention (campaign/newspaper); h = outpatient clinics, health centres; i = sudden deaths, very early death; j = emergency, ambulance, on call medical services; k = ICD-codes; l = door-to-door, home visit, social services, phone calls; m = autopsy reports.

  • §Studies providing the proportion of CT use in SAH patients exclusively, in contrast with % of CT in patients with stroke in general.

  • ¶Studies not providing the exact proportion of patients with CT exclusively, but only the proportion of patients investigated with CT, autopsy or MRI.

  • **CT was available after 1992, and before 1992, all patients were diagnosed with lumbar puncture or autopsy.

  • ††Additional diagnostic criteria, besides CT. For inclusion, at least A or B was necessary in pre-CT era or when CT percentage was below 90%. A = Lumbar puncture; B = autopsy; C = angiography; D = MRI; E = surgery.

  • ‡‡Proportion of patients investigated with CT or diagnostic criteria unknown, but inclusion after discussion among authors of this review.