Validation of the Swedevox registry of continuous positive airway pressure, long-term mechanical ventilator and long-term oxygen therapy

Magnus Ekström; Dirk Albrecht; Susanne Andersson; Ludger Grote; Birgitta Kärrsten Rundström; Andreas Palm; Jenny Theorell-Haglöw; Josefin Wahlberg; Bengt Midgren

doi:10.1183/23120541.00340-2020

Validation of the Swedevox registry of continuous positive airway pressure, long-term mechanical ventilator and long-term oxygen therapy

ERJ Open Res. 2021 Jan 18;7(1):00340-2020. doi: 10.1183/23120541.00340-2020. eCollection 2021 Jan.

Authors

Affiliations

¹ Lund University, Faculty of Medicine, Dept of Clinical Sciences Lund, Respiratory Medicine and Allergology, Lund, Sweden.
² Dept of Respiratory Medicine, Sunderby Hospital, Luleå, Sweden.
³ Respiratory Unit, Dept of Medicine, Hallands Hospital, Halmstad, Sweden.
⁴ Sleep Disorders Centre, Pulmonary Dept, Sahlgrenska University Hospital, Gothenburg, Sweden.
⁵ Center for Sleep and Wake Disorders, Institute for Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
⁶ Dept of Medical Sciences, Respiratory, Allergy and Sleep Research, Uppsala University, Uppsala, Sweden.
⁷ Centre for Research and Development, Uppsala University/Region of Gävleborg, Gävle Hospital, Gävle, Sweden.
⁸ Dept of Medicine, Blekinge Hospital, Karlskrona, Sweden.

Abstract

Background: The Swedish Registry of Respiratory Failure (Swedevox) collects nationwide data on patients starting continuous positive airway pressure (CPAP) treatment, long-term mechanical ventilator (LTMV) and long-term oxygen therapy (LTOT). We validated key information in Swedevox against source data from medical records.

Methods: This was a retrospective validation study of patients starting CPAP (n=175), LTMV (n=177) or LTOT (n=175) across seven centres 2013-2017. Agreement with medical record data was analysed using differences in means (sd) and proportion (%) of a selection of clinically relevant variables. Variables of interest included for CPAP: apnoea-hypopnoea index (AHI), height, weight, body mass index (BMI) and Epworth Sleepiness Scale (ESS) score; for LTMV: date of blood gas, arterial carbon dioxide tension (P _aCO₂ ) (breathing air), weight and diagnosis group; and for LTOT: blood gases breathing air and oxygen, spirometry and main diagnosis.

Results: Data on CPAP and LTOT had very high validity across all evaluated variables (all <5% discrepancy). For LTMV, variability was higher against source information for P _aCO₂ (>0.5 kPa in 25.9%), weight (>5 kg in 47.5%) and diagnosis group. Inconsistency was higher for patients starting LTMV acutely versus electively (P _aCO₂ difference >0.5 kPa in 36% versus 21%, p<0.05, respectively). However, there were no signs of systematic bias (mean differences close to zero) across the evaluated variables.

Conclusion: Validity of Swedevox data, compared with medical records, was very high for CPAP, LTMV and LTOT. The large sample size and lack of systematic differences support that Swedevox data are valid for healthcare quality assessment and research.