Friday, December 20, 2013

Collecting and Plotting Baby Data

When I was looking for a good app to start tracking Lele's activity, I selected the first one I could find, and it turned out to be great. It's called Feed Baby Pro for Android and it has all the features that I want:
  • Tracks feed data (length, frequency), diaper data, pumping data, sleep data, and medicine data (a flexible tracker that lets us label and track whatever else we want, like Tummy Times).
    • Bonus: Tracks weight and height, and plots against CDC percentile distributions.
  • Syncs with Will's phone (and an unlimited number of other Android devices), allowing both of us to log data points and review the day. This really helps us stay in sync about things like, when was the last time she ate?
  • Has really smart Widgets that make logging data easy. More on that below too.
  • Has pretty smart data visualizations. This is like crack for the MBA part of my brain. More on that below.
Awesome Widgets
 
Here's a screen shot of the new home view of my phone. I'll go from top to bottom describing each widget. Top left is which side I started the last feed on, as well as the start and end time. 

Widget right below it (the L/R buttons) are a shortcut to start timing a feed, depending on which side begins it. When the feed starts, the two top widgets change into a timer and the pause/stop buttons. Brilliant! 

Beneath the feeding widgets are three buttons to quickly record a diaper.

On the bottom row, I have my Gentle Alarm widget (from a separate app), then a shortcut to record medicine (we use it to track her tummy times and her baths, and also to record my postpartum meds). The green button with the pillows on it starts timing a sleep session (we don't record that; it was too much).

There's a ton of widgets, so you can customize them to record the data you gather most frequently. For example, Will has a bottle feed widget on his screen that I don't have on mine.

Data! Data! Data!

This is probably my favorite thing about this app: the data visualization is pretty awesome. 

For example, here's Alex's weight-to-age percentile for the first three weeks of her life, plotted against CDC percentiles:

From top to bottom:
  • Orange = 95th percentile
  • Purple = 75th percentile
  • Brown = 50th percentile
  • Green = 25th percentile
  • Blue = 5th percentile.
The red line is Alex's actual weight-to-age percentile. Note that she starts off beneath 25th percentile for her first week of life, then shoots up to above 50th percentile in the subsequent two weeks. Awesome.



One of my gripes with Alex's early days is that I always felt like I was feeding her nonstop.  Books say that newborns can nurse at intervals of 1-2  hours apart, for a length of time between 30-40 minutes total (about 15 minutes each side). This is because they're so little that 1) they have tiny stomachs that empty and need to be refilled very often, and 2) they don't have the muscles or learning to feed efficiently, so it takes foreeeeeever. Since intervals are timed (like contractions) at the start of each feed, on bad days in essence this can mean: feed 30 minutes.  Rest 30 minutes.  Feed 30 minutes.  Repeat.

Since then it's gotten a lot better, and the data bears this out. Here's a bar graph of the length of intervals between each session, for the past two weeks:



Note that the general trend is definitely towards a higher density of longer intervals, which means that I'm having more time between feeds to do things like shower.  It would be really great to have an "average session interval per day" line graph overlay, but that's not included. 

(In order to make that happen, I'd have to download my data into CSV format -- which you can absolutely do -- and then graph it myself. I'm really tempted to do so but already Will and my complete dedication to data gathering is a strong marker for nerd parents, and I don't want to push my luck).
The same story stands for Daily Session Counts (i.e., the number of times I'm feeding her per chunk of hours per day):


You can definitely see a downward trend. Again, no average line, but what can you do.

Finally, there's a feeds heat map:


The intensity of the red color indicates length of feed time, but that's not accurate anymore (I'm getting lazy). Y-axis is each day. X-axis is each hour of the day. Middle vertical line is 12 noon.

The diagonal patterns are kind of interesting because you can see her normal feed times migrating earlier (or later) as the days go on. Eventually, by Month 3 her nap times (and maybe even sleep times) are supposed to stabilize, so I'm assuming that will push her eating times to stabilize as well.  The heat map will be helpful then to start seeing if there are any regular patterns in her feeds.

Gotta love it!