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Making Change by Changing the Callascope

At GWHT, we are seeking to be change makers by taking creative action to solve social and global problems. One way we are creating change is through the development of the Callascope, a cervical cancer screening device.

A 2019 interview with Mercy Asiedu on the development of the Callascope

The Callascope just received an update, so we sat down with Dr. Mercy Asiedu again to discuss the changes and how the updated device fits in with the WISH model.


Tell me about the new Callascope! What updates or changes were made and why?

The callascope and images

The main update involves switching from using a 2 megapixel camera to using a 5 megapixel camera, because the 2 megapixel camera’s image quality wasn’t sufficient for the level of clarity and resolution that we needed while imaging the cervix. Initially, we weren’t using the 5 megapixel camera because of sizing issues (it’s much larger), so when we switched we had to change some of the design, which brings me to change number two.

In previous designs, the camera had an outer shell, which served as the device’s introducer/inserter. However, because we now have a bigger 5 megapixel camera, it didn’t make sense to have the camera and an additional outer shell. We were trying to keep the stem about the same size as the previous Callascope designs we’ve tested. Eventually, I came up with an integrated camera and shell. Now, the whole stem is the camera, and we have a removable tip that functions as the introducer. This is actually really cool, because it can easily go from being a speculum-free device that can be used for self-imaging (with the use of the tip as an inserter), to an imaging device that can be used with a traditional speculum (without the use of the tip).

The last significant changes we made were adding silicone to the tip to make it softer and more pleasant and adding custom LEDs that are much brighter, which allows for a much clearer picture of the cervix.


How did the principles of human-centered design play a role in the development of the device?

Human-centered design was employed much more obviously in the beginning and it hasn’t really changed since then. When we were making the original design, we worked with potential patients and providers. We provided them with a lot of prototypes, and they gave us feedback about what was most comfortable, what would be easy to use, etc. We learned a lot about comfort and ease of use compared to the speculum.

Most of our recent changes have been functional, which means we made those changes internally. The silicone tip, however, is something that really embodies the human-centered design process. Every time we tested the device — at Duke, in Ghana, and in Peru — patients always ask if the tip could be softer. We have always wanted to include the silicone tip; we wanted to incorporate this feedback and it made sense to us as women, but we couldn’t originally make changes due to a constraint on the resources available within the lab. Once we started working with Blur, who is our contract manufacturer, we were able to have access to better resources to ensure the silicone tip was included. It made sense for us to spend a bit extra incorporating the silicone tip once we had the resources to do that, as it is clearly very important to the patients.


This month we are talking about how to be a changemaker using our WISH model for health care. Can you explain how the device fits within the context of the WISH model, as well as the changes in health care that you would hope to see?

The WISH model has three main arms: women-inspired technology, community workforce training, and peer-to-peer learning. The Callascope fits in with all three of these arms.

The women-inspired technology arm of WISH employs first-of-their-kind technologies for at-home use as well as clinical-based diagnostics and treatment. The Callascope is a key player in this, as it allows for at-home imaging of the cervix. It can be used in conjunction with HPV self-sampling for cervical cancer screening by the patient in the comfort of their home. Especially in cases where privacy is key — let’s say there are a lot of male gynecologists in a culturally conservative region — the Callascope allows women to take initiative with regard to their health and improves access to screening services.

The Callascope can also be used for other health applications beyond cervical cancer screening, such as checking the cervix for infections, monitoring any cervical diseases outside of cancer (such as genital warts on the cervix), or checking the cervix’s dilation during labor, which can help women determine when to go to the clinic as opposed to when its a false alarm.

Community workforce training teaches women to begin the screening process themselves as well as training midwives and nurses to identify and treat disease before it advances to cancer. The Callascope fits in with this arm for a similar reason: by giving women a device like the Callascope, which allows for autonomy over one’s health, women begin the screening process at home without needing to come to a clinic. Those images can be sent to a clinic and if there is a reason that they do need to come in, that can be communicated.

Even if women don’t want to use the device themselves, midwives and nurses can use the device to screen without use of the speculum, which has been shown to deter women from going in to the clinic to get a screening. With these screenings, we can tell if a woman has high or low grade pre-cancer, which allows us to treat before advancement to cancer.

Peer-to-peer learning tries to address the feelings of fear or embarrassment that many women feel during the screening process. The Callascope provides an avenue for self-exploration and understanding, while simultaneously removing the pain associated with the speculum. When someone is screening themselves, they are less afraid of being in pain, and when they can screen themselves in private, they are less likely to experience feelings of embarrassment.

What we have also done with the Callascope is ask women to reflect on using the device and their feelings upon seeing their cervix. This kind of storytelling ties in directly with this arm of the WISH model, as women break down the shame and stigma associated with sexual and reproductive health.



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