Department of Obstetrics and Gynecology, University of Helsinki, and Helsinki University Hospital, Helsinki, Finland.
Department of Obstetrics and Gynecology, HUS Hyvinkää Hospital, Hyvinkää, Finland.
Acta Obstet Gynecol Scand. 2022 Nov;101(11):1245-1252. doi: 10.1111/aogs.14445. Epub 2022 Sep 3.
Despite the high prevalence of miscarriages, they are not systematically registered and few epidemiological studies have been done. As Finnish health registries are comprehensive and widely used in research, we validated the Finnish register data concerning diagnostics and treatment of miscarriage, and treatment-related adverse events.
We conducted a validation study regarding miscarriage-related codes of diagnoses and surgical procedures in a Finnish National Hospital Discharge Registry (NHDR) by comparing the information from the NHDR with that of the hospital records. We selected a random sample of 4 months during 1998-2016 from three hospitals, comprising 687 women aged 15-49 experiencing a first miscarriage during follow-up. Women with diagnoses unrelated to miscarriage, or proven to be other than miscarriage, were excluded. The final sample consisted of 643 women with confirmed miscarriage, which was used for analyses regarding the diagnosis, treatment and adverse events of miscarriage treatment.
The majority of miscarriages registered in the NHDR were confirmed by the hospital records (positive predictive value [PPV] = 93.6% [95% confidence interval [CI] 91.8%-95.4%]). Different types of miscarriage were also reliably identified; spontaneous abortion with PPV = 85.6% (95% CI 80.9%-89.2%), missed abortion with PPV = 92.7% (95% CI 88.8%-95.3%) and blighted ovum with PPV = 91.1% (95% CI 84.3%-95.1%). The PPV of surgical treatment (62.2% [95% CI 55.7%-68.3%]) was lower than the PPV of non-surgical treatment (93.3% [95% CI 90.5%-95.3%]). The diagnoses regarding adverse events of miscarriage treatment could be reliably identified. The PPV for clinical infections was 76.0% (95% CI 56.6%-88.5%) and for retained products of conception or/and vaginal bleeding 96.8% (95% CI 83.8%-99.4%).
The coverage of the NHDR was good concerning identification of miscarriages, different types of miscarriages and non-surgical treatment. Nevertheless, there is a need for clearly defined procedural codes concerning to medical treatment of miscarriage. The register-based data are reliable and practicable for both clinical evaluation and research concerning miscarriage.
尽管流产的发生率很高，但它们并未被系统地登记，而且很少有流行病学研究对此进行过研究。由于芬兰的健康登记系统全面且广泛应用于研究中，我们对芬兰国家住院患者出院登记系统（NHDR）中有关流产诊断和治疗以及与治疗相关的不良事件的登记数据进行了验证。
我们通过将 NHDR 中的流产相关诊断和手术程序信息与医院记录进行比较，对芬兰 NHDR 中的流产相关诊断和手术程序信息进行了验证研究。我们从三家医院中选择了 1998 年至 2016 年的 4 个月作为随机样本，包括 687 名年龄在 15-49 岁之间的女性，在随访期间经历了首次流产。排除了与流产无关的诊断或经证实非流产的女性。最终样本包括 643 名经证实的流产女性，这些女性被用于分析流产的诊断、治疗和治疗相关的不良事件。
NHDR 中登记的大多数流产都得到了医院记录的证实（阳性预测值[PPV]为 93.6%[95%置信区间[CI]为 91.8%-95.4%]）。不同类型的流产也得到了可靠的识别；自然流产的 PPV 为 85.6%（95%CI 为 80.9%-89.2%），稽留流产的 PPV 为 92.7%（95%CI 为 88.8%-95.3%），空孕囊的 PPV 为 91.1%（95%CI 为 84.3%-95.1%）。手术治疗的 PPV（62.2%[95%CI 为 55.7%-68.3%]）低于非手术治疗的 PPV（93.3%[95%CI 为 90.5%-95.3%]）。与流产治疗相关的不良事件的诊断也可以得到可靠的识别。临床感染的 PPV 为 76.0%（95%CI 为 56.6%-88.5%），残留产物或/和阴道出血的 PPV 为 96.8%（95%CI 为 83.8%-99.4%）。
NHDR 在识别流产、不同类型的流产和非手术治疗方面的覆盖率良好。然而，仍需要明确有关流产医疗处理的程序性代码。基于登记的数据集对于流产的临床评估和研究都是可靠且可行的。
