Software Glitch over DST Birthdates

A news item that reminds us of the importance of software validation, especially in cases where patient records may have birthdates impact by Daylight Savings Time (DST):

Paul Eggert commented in The RISKS Digest Volume 32 Issue 16 on a recent issue with delays with hospital lab tests due to software “bugs.”  The author cited a recent paper published today by the Journal of Applied Laboratory Medicine, where Andrew Lyon and collaborators describe a series of crashes in a hospital lab information system that used handheld wireless devices to identify patients in the Jim Pattison Children’s Hospital, which opened last year in Saskatoon, Saskatchewan. JPCH has pediatric and maternal services, and also has an emergency room. The SoftID-based system first crashed 19 days after installation, and continued to crash roughly every two weeks thereafter. Lab staff reverted to paper procedures during crashes.

To help diagnose the crashes, the hospital’s support team sent logs to the SoftID developers, who eventually tracked the problem down to elderly patients with birthdays like April 13, 1941, a day when most of Saskatchewan’s clocks sprang forward at midnight due to a daylight-saving time transition. A patient with birthday on that date would have their birth time default to 00:00, a time that did not exist in Saskatoon because the clocks had already been switched to 01:00. The Joda-Time software within SoftID used the IANA time zone database to translate times, and crashed because the local time was invalid. Lyon et al. suggest several takeaways from this software glitch, including:

• A DST transition can disrupt hospital operations long after the transition.
• Hospital software and hardware systems should be validated by test-patient records with birth dates on daylight-saving transitions.

Similarly, in an article in the The Journal of Applied Laboratory Medicine, published July 30, 2020, the authors describe The JPCH phlebotomy team’s implementation of SoftID®: An optional module of the laboratory information system (LIS) [SCC Soft Computers] that uses handheld wireless devices for positive patient identification. SoftID® was initially released in 2009 but had not been installed locally. The SoftID® system gathers pending laboratory orders electronically placed in the LIS by ward staff via a hospital information system and allows bedside printing of laboratory bar-code labels to improve collection efficiency while reducing the risk of specimen mislabelling. Software crashes led to an investigation, which found source of problem could be related to the date and time of birth information for specific patients and daylight savings time (DST). Could software validation have prevented this?

Read more SoftwareCPR articles on software validation here: Warning Letter – Inadequate software validation, Warning Letter – Software Validation Shortcomings, $SoftwareCPR QS Validation Form Training Example $