Estimation of date of confinement: should paper gestational age wheels be abandoned?




We read the interesting and important study by Chambliss and Clark where the estimated date of confinement (EDC) obtained from paper gestational age wheels was compared with that calculated using electronic techniques (APPs) downloadable to mobile/smart phones. The majority of mechanical wheels studied did not generate the correct EDC although all the APPs did. Also, the EDC obtained from wheels of similar sources differed. The authors in their conclusion suggested that paper gestational age wheels should be abandoned. This recommendation may not be of public health interest particularly in low and middle income countries (LMIC) and has the potential of leading to more medical errors.


Paper gestational age wheels are cheap and readily available for use in LMIC. Every healthcare worker in LMIC may not be able to afford a smart phone. The provision of smart phones (with downloadable APPs to calculate EDC) by Health Care Authorities in LMIC may have huge cost implications and redirect finances from essential health services. Abandonment of paper gestational age wheels by facilities that cannot afford appropriate mobile phones will therefore force healthcare workers to calculate EDC off by heart. This is prone to error in a busy unit if the health personnel are not used to such tasks.


The use of smart phones’ APPs has other limitations. Because smart phones are expensive, they are prone to being stolen despite their capabilities of being tracked and/or blocked if lost. Although attending to pregnant patients, the battery charge of a phone may be low and not able to power the device for the APPs to be used. The situation will even be more frustrating if there is no immediate means of charging the battery. Furthermore, some health workers may require extra training to learn how to use smart phones and their APPs.


It is possible that wear and tear following prolonged usage of paper mechanical wheels evaluated in the study led to incorrect EDC they generated. Likewise, faulty mobile phones/APPs will also give wrong EDC.


Rather than the abandonment of paper gestational age wheels, stringent quality check should be introduced to ensure that reliable products are manufactured. Even in settings where APPs are available, calculation of EDC by any 2 of paper wheel, APPs or off by heart methods will assist in cross-checking the result of each against the other to prevent error. This may be the most appropriate approach.

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May 10, 2017 | Posted by in GYNECOLOGY | Comments Off on Estimation of date of confinement: should paper gestational age wheels be abandoned?

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