# Cologuard. Yeah. That thing. **URL:** \ **Category:** In My Humble Opinion\ **Created:** [September 4, 2017, 8:00pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502 "2017-09-04T20:00:36Z")\ **Posts on this page:** 17\ **Page:** 2
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [September 5, 2017, 11:29pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/21 "2017-09-05T23:29:16Z")
> [@Senegoid](#): > > … **DSeid** , am I on the right track? > > I guess that, having had a full colonoscopy that finds nothing, or finds very little, then the likelihood of actually having a problem in the next ten years is much reduced. I take this to mean that subsequent FIT tests don’t have a greater chance of positive results, but only that those positive results have a greater chance of being false. Am I thinking a-right here? Yes. Exactly. An all clear colonoscopy means extremely low probability of something forming and becoming a higher grade cancer in the next ten years. IOW the odds of a true positive are low but there will be just as many false positives. Which would require an early repeat colonoscopy. ---
**Author:** ![Grumbacher\_Red](https://avatars.discourse-cdn.com/v4/letter/g/85e7bf/32.png) [@Grumbacher\_Red](https://boards.straightdope.com/u/Grumbacher_Red)\ **Post date:** [September 5, 2017, 11:42pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/22 "2017-09-05T23:42:29Z")
After much pestering from my Doc, I finally broke down a few months ago and had a colonoscopy, and it was so much less of a big deal than I had imagined it to be. I got an all clear, so I am good for some years to go now. However, my first reaction for 3 years when she started pushing me to have the scope was, “Can’t I just poop in a box?” I was all for pooping in the box, but now, I am glad she didn’t let me, and I have the peace of mind of being scoped. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [September 5, 2017, 11:58pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/23 "2017-09-05T23:58:23Z")
> [@Doctor\_Jackson](#): > > Despite my screen name, IANAD IRL. That said, I do have experience with Cologuard and have done a substantial amount of research. I think the question is “Why do an invasive procedure of any kind when it’s not necessary?” > > A good, well cited article on Cologuard at [gastro.org](http://www.gastro.org/news_items/cologuard) says, in part: > > In my age bracket there is a 6% chance of a false positive, in which case one schedules a colonoscopy. Conversely, 94% of the time the invasive procedure is not needed. YMMV. And I am not a gastroenterologist. OTOH I do not get paid by the makers of Cologuard, Exact Sciences, to promote it as the author of your cite does. Another well cited article, by someone who is not a paid consultant, [http://www.medpagetoday.com/gastroenterology/generalgastroenterology/47428](http://www.medpagetoday.com/gastroenterology/generalgastroenterology/47428) gives slightly different false positive numbers and on phone so not chasing original articles right now but they both agree that the FIT’s false positive rate is less (5%). If one wants to avoid colonoscopy then choosing the approach with the lower false positive rate makes the most sense to me. Yes, most negative results with either test will be true negatives as most of us do not have colon cancer at the time of screening. ---
**Author:** ![Doctor\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doctor_jackson/32/32_2.png) [@Doctor\_Jackson](https://boards.straightdope.com/u/Doctor_Jackson)\ **Post date:** [September 6, 2017, 1:56pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/24 "2017-09-06T13:56:29Z")
> [@DSeid](#): > > And I am not a gastroenterologist. OTOH I do not get paid by the makers of Cologuard, Exact Sciences, to promote it as the author of your cite does. I was looking for a quick, plain language cite and made the mistake of not reading the disclaimer. I will point out, however, that disclosed interest does not necessarily indicate wrong analysis. It is certainly cause for follow up. > [@DSeid](#): > > Another well cited article, by someone who is not a paid consultant, [http://www.medpagetoday.com/gastroenterology/generalgastroenterology/47428](http://www.medpagetoday.com/gastroenterology/generalgastroenterology/47428) gives slightly different false positive numbers and on phone so not chasing original articles right now but they both agree that the FIT’s false positive rate is less (5%). I can’t get tot that cite without registering. Here’s a link to the [FDA study](https://www.accessdata.fda.gov/cdrh_docs/pdf13/P130017b.pdf)that these articles are likely based on. Diagnostic yield charts begin on page 41. > [@](#): > > The primary risk associated with the Cologuard test is a false assay result (i.e., a false positive or a false negative result). The Cologuard false negative rate was estimated to be 7.7%. The total positivity rate for Cologuard is estimated to be 16%. Considering all positive results, approximately 1 of 4 positive results is predicted to result in a diagnosis of CRC or AA. Thus, in a hypothetical population of 100,000 users, Cologuard would identify 129 more CRC cases and 1412 more AA cases compared to use of FIT and for every 59 additional false positive results > compared to FIT, use of Cologuard would be associated with identifying 12 more true positives Personally, I’m comfortable enough with the numbers to rely on the non-invasive testing as my primary test. Others, particularly with higher risk facfors, may not be. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [September 6, 2017, 10:07pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/25 "2017-09-06T22:07:48Z")
I did the deed and sent the kit off this afternoon. I’ll let everyone know about the results when I get them. I also have a mammogram scheduled for Friday, so I guess I have my bases all covered. 🆒 ---
**Author:** ![Doctor\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doctor_jackson/32/32_2.png) [@Doctor\_Jackson](https://boards.straightdope.com/u/Doctor_Jackson)\ **Post date:** [September 7, 2017, 12:50pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/26 "2017-09-07T12:50:58Z")
Do you still have to go in for that, or can you ship your boobs off in a box? :eek:😃 [sub]Mammoguard?[/sub] ---
**Author:** ![Kimballkid](https://avatars.discourse-cdn.com/v4/letter/k/b5a626/32.png) [@Kimballkid](https://boards.straightdope.com/u/Kimballkid)\ **Post date:** [September 7, 2017, 6:54pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/27 "2017-09-07T18:54:35Z")
> [@aceplace57](#): > > I have GERD and they scoped both ends last time. Hopefully, not at the same time. Or with the same scope. 😃 ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [September 8, 2017, 2:26am UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/28 "2017-09-08T02:26:34Z")
> [@Doctor\_Jackson](#): > > Do you still have to go in for that, or can you ship your boobs off in a box? :eek:😃 > > [sub]Mammoguard?[/sub] There are a gazillion cartoons that are variations of the “Man-O-Gram”. 😃 😛 ---
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [September 8, 2017, 3:31am UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/29 "2017-09-08T03:31:06Z")
> [@Roderick\_Femm](#): > > Never mind, misread the OP. As Color Guard? I only opened the thread because even after someone trying to explain, I don’t understand what color guard is. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [September 8, 2017, 7:46am UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/30 "2017-09-08T07:46:08Z")
> [@elfkin477](#): > > As Color Guard? I only opened the thread because even after someone trying to explain, I don’t understand what color guard is. It’s the guy who carries the flag at the head of the parade, and several additional guys surrounding him. It’s their job to prevent spectators from splashing Clorox on the flag. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [September 8, 2017, 8:57pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/31 "2017-09-08T20:57:48Z")
Today’s mammogram was postponed because the machine was malfunctioning. :o ---
**Author:** ![Ignatz](https://avatars.discourse-cdn.com/v4/letter/i/3be4f8/32.png) [@Ignatz](https://boards.straightdope.com/u/Ignatz)\ **Post date:** [September 8, 2017, 10:06pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/32 "2017-09-08T22:06:08Z")
> [@Kimballkid](#): > > Hopefully, not at the same time. Or with the same scope. > > 😃 After my fourth and last colonoscopy I asked the doc if doing both ends during the same visit and anesthesia was feasible (as I have GERD & Barrett’s E as well) to avoid having to get a round trip ride to/from the gastro center at two different visits. He said yes and added that they use different equipment. I never took it up with him (or down) again. Or with anyone else. (Not because of that answer-I’m too old.) ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [September 9, 2017, 5:08pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/33 "2017-09-09T17:08:28Z")
> [@Doctor\_Jackson](#): > > I was looking for a quick, plain language cite and made the mistake of not reading the disclaimer. I will point out, however, that disclosed interest does not necessarily indicate wrong analysis. It is certainly cause for follow up. > > I can’t get tot that cite without registering. Here’s a link to the [FDA study](https://www.accessdata.fda.gov/cdrh_docs/pdf13/P130017b.pdf)that these articles are likely based on. Diagnostic yield charts begin on page 41. > Personally, I’m comfortable enough with the numbers to rely on the non-invasive testing as my primary test. Others, particularly with higher risk facfors, may not be. Sorry for the delay in response. Yes, that is the study as published here in [The NEJM](http://www.nejm.org/doi/full/10.1056/NEJMoa1311194#t=article) as well. As a one time test it will miss a significant finding (defined as cancer or an advanced precancerous lesion) 7.7% of the time. For all age groups it will miss the advanced precancerous lesions a majority of the time. After a single screening you’ll also have to have colonoscopy after the test anyway about 16% of time which will be completely normal three out of four times (and btw [take longer than normal](http://www.jwatch.org/na43058/2016/12/16/positive-cologuard-test-makes-longer-colonoscopy-time)). Done every three years that means that the majority of the time you’ll have a colonoscopy within the decade anyway. But yes, the stool screening tests both can avoid colonoscopy _some_ of the time, and it is not crazy for a low risk individual decide that having a nearly 50% chance avoiding colonoscopy for the decade is worth the marginally increased risk of a missed signifiant finding. Not my personal choice as a low-risker, to me colonoscopy was and in a couple more years will be no big deal, but I get why some choose that. Just the arranging for someone to be there to take you home can be a major issue for some people! The question in my mind why Cologuard every three years over annual FITs? It does _not_ seem like a Cologuard-based program would decrease the number of colonoscopies needed over a FIT-based program (seems more likely to increase the number) nor would as a complete program does it seem like it would find more significant lesions (could be more, could be less, we really just don’t know in a head to head done that way). The two programs, done as advised, _both_ offer a nearly 50% chance of avoiding a colonoscopy for the decade at some marginally increased risk of missing something significant over the decade. One is tried and true with a long track record and is dirt cheap, easy to remember to just do annually with a very simple collection procedure, and one is new, much much more expensive (even if insurance picks up the tab we all pay for it) and requires remember to do it that every third year (a bit harder than just every birthday or first day of Spring or whatever). One is heavily advertised by a for profit company and has company-paid consultants out selling it. Which one seems the better one for the population as a whole? What makes the Cologuard worth the extra expense to us a population or to any individual? ---
**Author:** ![Mama\_Zappa](https://avatars.discourse-cdn.com/v4/letter/m/71e660/32.png) [@Mama\_Zappa](https://boards.straightdope.com/u/Mama_Zappa)\ **Post date:** [September 10, 2017, 10:14pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/34 "2017-09-10T22:14:59Z")
> [@Senegoid](#): > > … > And what has happened since? For whatever reason, once one has the REAL THING, they no longer do the mail-order tests, but instead tell me to have the full colonoscopy done again once every ten years. > > 😕 0 Interesting. I’ve had numerous “real thing” colonsocopies and have never been recommended the Cologuard, but I would not be in the target population anyway as I’m higher risk. Re the OP: If you’re low risk, I’d say go for it :D. It’s a LOT less effort (judging from having to do an occult stool test myself decades back) than prep for the real thing. Obviously, if it turns up anything suspicious, you get the extra special inspection… ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [September 10, 2017, 10:32pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/35 "2017-09-10T22:32:42Z")
It’s easy. No big deal. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [September 13, 2017, 6:27pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/36 "2017-09-13T18:27:39Z")
> [@nearwildheaven](#): > > Today’s mammogram was postponed because the machine was malfunctioning. :o I had the rescheduled one yesterday, and they want me to have a follow-up with the radiologist present because they found something that warrants further examination. ☹ I’m having that done next week. I know it’s probably nothing to worry about, but I still do. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [October 19, 2017, 9:19pm UTC](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502/37 "2017-10-19T21:19:31Z")
I’m sure glad I had that mammogram, because they found a small cancer. More details can be found in my thread about it. I also had to do the Cologuard over because my first specimen was too large, and got the results from the do-over earlier today. All clear! 🆒 At least things look good from THAT end (no pun intended). [Previous page](https://boards.straightdope.com/t/cologuard-yeah-that-thing/795502.md?page=1)