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The outcome of a Swedish mammographic screening programme has been studied by analysis of official health statistics for 1987-96. The study series comprised 605,260 women (70 per cent of those aged 50-69 years at inclusion in the mammography programme), representing 4,908,176 woman-years, 1,932,353 mammographies, and 6,713 deaths due to breast cancer. The observed number of deaths was 55 (0.8%) less than would have been expected had the screening not been performed (ns), whereas findings in the Two County Council study suggest that the reduction in mortality should have been 28 per cent (n = 739) for the group and period studied. Thus, the cost of saving a single life was estimated to have been SEK 18-25 million (approximately GBP 1.3(1.8 m. USD 2.36(3.17 m).

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That sumatriptan tablets are effective and well tolerated in the acute treatment of migraine has been established, but the relationship between dose and efficacy has not been adequately defined to date in clinical trials. This multinational double-blind trial (N = 1003) in which patients treated up to three migraine attacks with sumatriptan 25 mg, 50 mg, 100 mg, or placebo, with a second independently randomized dose for headache recurrence, evaluated the efficacy and tolerability of three doses of sumatriptan. The results demonstrate that all doses of sumatriptan were superior (P < 0.05) to placebo in reducing moderate or severe predose headache to mild or no headache 4 hours postdose for each of the three treated attacks; sumatriptan 50 mg and 100 mg were each superior (P < 0.05) to sumatriptan 25 mg 4 hours postdose for two of three attacks. Sumatriptan (all doses) was similarly effective at relieving nausea and photophobia or phonophobia or both and at reducing clinical disability. Headache recurrence was experienced by similar proportions of patients across treatment groups (35% to 48% after placebo; 26% to 39% after sumatriptan). Relief of recurrent headache 2 hours after the second dose of study medication occurred in greater percentages of patients using any dose of sumatriptan compared with patients using placebo to treat recurrence. The incidence of adverse events with 25-mg and 50-mg sumatriptan tablets was similar to the incidence with placebo and lower than the incidence with 100-mg sumatriptan tablets. These data provide the first demonstration from a large well-controlled clinical trial that both the 50- and 100-mg doses are more effective than the 25-mg dose and that the 50-mg dose is associated with a lower incidence of adverse events than the 100-mg dose.

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Fifty-eight patients, 31 women and 27 men, with a wide range of upper arm circumferences (20-43 cm), ages (16-82 years) and body mass indices (16-55 kg m-2) were studied. The direct blood pressure was measured in the brachial artery in one arm and simultaneously the indirect pressure was measured in the other arm using a large standard cuff (rubber bag 12 x 35 cm). The mean intra-arterial blood pressure was (systolic/diastolic) 137 +/- 25 mmHg (SD)/76 +/- 10 mmHg. With the cuff the mean blood pressure was 134 +/- 23 mmHg/85 +/- 11 mmHg. The cuff significantly underestimated the systolic blood pressure (3.2 +/- 11.4 mmHg, range -25-30 mmHg) while the diastolic pressure was overestimated significantly (8.8 +/- 8.5 mmHg, range -32-14 mmHg). The direct/indirect blood pressure difference correlated significantly to the intra-arterial systolic and diastolic pressures (systolic/diastolic; r = 0.44, P = 0.0006/r = 0.36, P = 0.0062), but only to the auscultatory diastolic pressure (r = -0.02, P = 0.9/r = -0.45, P = 0.0004). The direct/indirect difference correlated significantly to the arm circumference (r = -0.33, P = 0.01/r = -0.30, P = 0.02) as did the diastolic direct/indirect difference to pulse rate (r = 0.34, P = 0.009). Age did not correlate significantly to the direct/indirect blood pressure difference in this study (r = -0.02, P = 0.9/r = -0.10, P = 0.5). It can be concluded that in addition to the ratio between the arm circumference and the width of the cuff (rubber bag), there are other sources of systematic errors of indirect blood pressure measurement, in particular pulse rate and the level of indirect blood pressure. If corrections could be made with regard to these variables, it is obvious that the reliability of the indirect method, especially when used in epidemiological contexts, would increase.

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We studied 20 patients with moderate to severe obesity (body mass index 37 +/- 8 kg/m2) with obese arms (arm circumference 37 +/- 4 cm). Their blood pressure was measured directly in the brachial artery in one arm and simultaneously indirectly in the other arm using either a large standard cuff (rubber bag 12 x 35 cm) or a new cuff (the Tricuff, Pressure Group AB, Stockholm) containing three rubber bags of different sizes, which automatically selected the appropriately sized bag in relation to arm circumference. Both cuffs showed a significant overestimation of the diastolic blood pressure (standard cuff 13 mm Hg, P < .001, Tricuff 6 mm Hg, P < .01). The error of the standard cuff was significantly greater than that of the Tricuff (P < .001). The differences in systolic blood pressure between the intraarterially and the indirectly measured results were small (0.2 to 3 mm Hg) and not statistically significant with either cuff. The new Tricuff offered an advantage as compared to a large standard cuff in terms of a lesser overestimation of the diastolic blood pressure. In practical terms, this should lead to a reduction in the overestimation of diastolic hypertension in obese individuals.

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This study compares blood pressures measured with a standard cuff (rubber bag 12 x 35 cm) with concomitantly measured intra-arterial pressures in 48 subjects. With the standard cuff, and using a diagnostic cut-off limit for diastolic hypertension of 90 mmHg, 15/48 patients were found to be hypertensive, whereas only 4/48 had intraarterial pressure above 90 mmHg. Thus, the specificity of the non-invasive method was only 75%. If higher diagnostic cut-off limits were used, e.g. 95 mmHg, specificity increased to 84%, and with lower cut-offs specificity was 63% for 85 mmHg and 52% for 80 mmHg. A specificity of only 75% is very poor for a method commonly used in screening examinations and may lead to considerable over-diagnosis of mild hypertension.

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In 48 individuals with a wide range of arm circumferences blood pressure measured indirectly with two different cuffs was compared to direct intraarterial measurements. The two cuffs were a standard size cuff (12 X 35 cm) and a newly developed cuff, containing three rubber bags of different sizes, which automatically selects the appropriately sized bag in relation to arm circumference (Tricuff, Pressure Group AB, Sweden). The Tricuff correctly placed 42 of the 43 patients in the "normotensive" range, ie, diastolic blood pressure less than 90 mm Hg, whereas the standard cuff put only 33 of 44 patients in this range (P less than .005). The discrepancy was not only due to the expected better performance in patients with obese arms, but also in the subgroup of patients with arms in the range 22 to 31 cm, in which group both cuffs would measure blood pressure with a 12 cm wide rubber bag. The number of correctly identified "normotensive" patients was noticeably higher with the Tricuff than with the standard cuff (30/31 v 25/32, P = .053). The better specificity of the new cuff thus offers an improvement over the standard cuff. There are several potential clinical advantages of this, mainly that the risk of erroneously labelling normotensive individuals as hypertensive is reduced.

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