Many (medical) students and residents and certainly also patients use the internet as a source of background information. A recent study reported the quality of health information regarding urolithiasis on the internet concluded however that a significant proportion of the information was biased.1 Urodynamic testing is done to objectively assess the dysfunction(s) that cause signs or symptoms of dysfunction, and requires physical measurements. Clinical measurements of (patho-) physiology comparable to urodynamics (e.g. lung-function, neurophysiology, cardio-physiology) are standardized and quality controlled. Urodynamics should be no exception with regard to standardisation and measurement quality. Urodynamic graphs are, apart from on internet sites, also published in the expert literature. We compared a sample of -peer reviewed- published urodynamic graphs with the technical quality of urodynamic graphs on the internet according to quality-items mentioned in the ‘ICS Good Urodynamic practice 2016’.

Google replies ≈600.000 results on ‘urodynam*’ and almost 1000 figures in the specific search option. Within the first 360 hits were 65 urodynamic graphs. PubMed replies >600 graphs when ‘urodynam*’ is searched in the (PubMed-) ‘images’ option. 36 within the first 400 figures were urodynamic graphs.  Screenshots of these are saved march 11, 2018. Almost all these urodynamic graphs on internet are published before the publication of the ICS Good Urodynamic Practice 2016, in June 2017, although criteria for technical quality have been available in the earlier ICS urodynamic practice standard of 2002. Good urodynamic practice necessitates to control that initial –baseline- pressures are in the physiological range and that filling sensations and permission to void are indicated. Furthermore vesical and intraabdominal pressures should respond with equal amplitude (balanced) on abdominal pressure rises (coughing, talking, breathing, moving) and should measure an ‘alive’-signal (breathing rhythm visible) throughout the test and furthermore: catheters should not slip out during the test.

11-14% of the graphs complied positive with all quality control items. Especially the frequent observation of baseline pressures outside the expected range, on the other hand, gives cause for concern as well as the number of graphs with pressures not or not adequately responding to abdominal (peak) pressure incidents. Sensation of bladder filling is relevant, both as a measure for bladder afferent abnormalities as well as a guidance to prevent overfilling, but is very frequently not visibly marked on the graphs. There was no difference between the graphs retrieved with Google or those obtained via PubMed.

Especially systematic zeroing to atmosphere seems not adhered to. Baseline pressures visible on the graphs are too low and or very uneven in almost 80% of shown cases/traces. When pressures are nevertheless responding in a balanced way (which has been the case in ≈65% of graphs) this should not have consequences for the pressure pattern of the cystometry. If pressures are used however, for leak-point pressure, detrusor (over) activity pressure, compliance or for pressure flow -analysis, the resulting detrusor pressures have become unreliable towards the known reference pressures. None of the legends provided with the graphs has included a comment on the quality of the graph. Regrettably, peer review has not demonstrably resulted in relatively more good quality urodynamic graphs. Urodynamic graphs available on the internet (sometimes specifically published with the goal to educate) and or graphs published in the peer reviewed medical literature are frequently not adhering to the ICS standard and therefore not suitable for (self-) education of urodynamic patterns. Many graphs do not help increasing the understanding of lower urinary tract physiology and also not the better understanding of lower urinary tract patho-physiology and dysfunctions, because of technical faults.

Many urodynamic graphs, both on internet as well as in scientific literature show imperfections when compared with good urodynamic practice criteria. Overall, only a minority of measurements that are (electronically) published were of good quality. The technical quality difference between peer reviewed and not peer reviewed urodynamics is negligible and the absence of explanation and discussion of visual (technical) features in the legends of the graphs hinders (self) education.

The table shows the percentages of graphs with the (good) quality features, mentioned here above present:
 * both ≈80% when end of filling is interpreted as ‘permission’ **during entire measurement.

Chang DT, Abouassaly R, Lawrentschuk N. Quality of Health Information on the Internet for Urolithiasis on the Google Search Engine. Adv Urol. 2016;2016:8243095. doi:  10.1155/2016/ 8243095. Epub 2016 Dec 4. PubMed PMID: 28044076; PubMed Central PMCID: PMC5164884
Rosier PFWM, Schaefer W, Lose G, Goldman HB, Guralnick M, Eustice S, Dickinson T, Hashim H. International Continence Society Good Urodynamic Practices and Terms 2016: Urodynamics, uroflowmetry, cystometry, and pressure-flow study. Neurourol Urodyn. 2017 Jun;36(5):1243-1260. doi: 10.1002/nau.23124. Epub 2016 Dec 5. Review. PubMed PMID: 27917521.
Schäfer W, Abrams P, Liao L, Mattiasson A, Pesce F, Spangberg A, Sterling AM, Zinner NR, van Kerrebroeck P; International Continence Society. Good urodynamic practices: uroflowmetry, filling cystometry, and pressure-flow studies. Neurourol Urodyn. 2002;21(3):261-74. PubMed PMID: 11948720.