Page 77 - Timeliness of Infectious Disease Notification & Response Systems - Corien Swaan

Timeliness of notification systems: a systematic literature review 75
clinical systems and several laboratory tests resulting in notifications complying with case definitions which will reduce the workload for both public health ser- vices and physicians considerably. [60] Another interesting development in ru- ral, resource poor settings is the use of mobile phone reporting. The studies of Quan et al and Rosewell et al showed that mobile phone reporting using SMS, shortened reporting time compared with conventional paper-based reporting and follow up from 37 to 7 days (medians) and from 84 to 2.4 days (averages) in South Africa and Papua New Guinea respectively [43, 58]. This methodology is simple, user friendly, reliable, and technically feasible in rural areas. It might be interesting to consider the use of mobile phone texting in addition to existing sophisticated notification systems in situations of newly emerging diseases or enhanced surveillance in high income countries as well.
Limitations
Studies used different parameters to calculate timeliness of their notification systems. In case the median, percentiles or means were used, we had to classi- fy the score according to the percentage of notifications within timeframes. In case of doubt, or when the score was close to the cutoff of 50% or 80%, a sec- ond author was consulted to come to a decision. Also the opinion of the authors of the study reflected in the paper was used to come to a score.
Some studies used the delay between specimen collection at the laborato- ry and notification at the local health departments. These delays were included as D2 as well, even though the test result was not yet available, in order to limit the number of different delays used in this study. It is noteworthy that eight studies, while presenting the delays of their notification system, did not include a predefined timeframe, either mandatory or chosen by the authors of the study. Also in several studies there was a difference between the mandatory timeframe and the timeframe chosen by the authors, without explanation. A realistic mandatory timeframe should be developed. It might be good to add a standardized timeframe, at least for D3 and D4-5, mostly affected by the notifi- cation system, in the Joint External Evaluation tool by the WHO.
The cut-offs in the scoring and delays in the standardized timeframe have been chosen on the above described grounds, but still are based on the opinions of the authors of this study. We consider 80% of timely notifications demon- strating a sufficient system, and 80% is in line with the WHO standard for an indicator based surveillance system [14], however an early warning system with 1/5 notifications not timely can cause considerable effect on effective control measures. When applying a 90% score as sufficient, the studies with sufficient
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