Page 30 - Diagnostic delay of endometriosis

referral (p =0.571). Time from referral to a gynaecologist to diagnosis was not influenced by presenting symptoms, previous treatment, or by other diagnoses that were considered first.
Discussion
This study shows a median diagnostic delay of 89 months or 7.4 years from first presentation of symptoms to the diagnosis of endometriosis. Previous studies in different European countries show a comparable diagnostic delay. This delay is a combination of patient’s and doctor’s delay. The patient’s delay, with a median length of 7 months, is comparable with previous studies. The most striking result in this study is the long delay caused at the doctor’s end. The median GP interval in this study was found to be 35 months, which is by far the largest part of the total delay in diagnosis. Compared to previous reports, we show a relatively long GP interval and a relatively short gynaecologist interval.15,19,20,23 We hypothesize that this finding can be explained by the position of the GP in the Dutch healthcare system. Women who are referred to a gynaecologist have a relatively high probability of suffering from a disease. In a healthcare system in which the role of the GP is absent or less prominent, the gynaecologist is consulted by an unselected patient population. In such a healthcare system, the same difficulties may be encountered in distinguishing between healthy and ill individuals as in the GP-centred situation in the Netherlands.
Diagnostic delay is shown as the median, because the length of the diagnostic delay is not distributed normally. By using this method, the influence of outliers is decreased. This also explains why the intervals do not add up to the total diagnostic delay.
In this study, selection bias may be present because women, responding well to oral contraceptives or analgesics prescribed by their GP may not have been diagnosed with endometriosis, have not been referred to a gynaecologist, and therefore, are not included in this study. Besides that, patients with symptoms that have not been recognized by the GP or by the gynaecologist will not have been diagnosed and have not been included in the study either. Prescription of oral contraceptives or pain relief by the GP is associated with a significantly longer time interval from first GP visit to referral to a second- line medical specialist, resulting in an extended overall diagnostic delay. This finding may be a consequence of the alleviation of symptoms by these drugs,
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