Purpose of a Baseline
The purpose of having a baseline is to compare the current weight against the baseline weight. Without a point of reference, all you can do is compare a current weight to a previous weight. And that simple math just doesn't provide enough information to make an informed decision about what is happening with your pet's weight.
A baseline weight takes some trending into account.
But because all pets are different--even within the same species, breed, gender and age--we cannot assume any statistic of 'average' for a pet. So, the baseline must be calculated on the values of your pet's weight. Initially, it will take some time and some weight points to get your pet's baseline well established. Therefore you should NOT wait until your pet is in a health crisis to start weighing them. In that case, the baseline will not be helpful yet. The sooner you start weighing your pet the better. And the more consistent you are in your weighing habits, the better your results will be.
You should weigh your pets weekly. Most pet welfare experts will advise you to weigh your pets weekly. Some people will say that is not necessary--that you can weigh monthly instead. It depends on how serious you are about your pet's health and well-being. If you only weigh your pet once a month, you are basically keeping a log of their weight--which is fine, but in that case, you are not monitoring them for health. If you allow an entire month to go by before you realize that your pet has been steadily declining week after week--you miss the opportunity to get your pet to vet or to realize there is some problem with their care or health. Waiting too long could cost your pet its life and can also cost you much more in vet fees by letting a condition go that could have been treated earlier.
When you get a weight alert in the care chart, it is just that -- an alert. It's time to pay much closer attention to what is happening with your pet. You must always use your own judgement. The Care Chart just provides you with a means to track the information. How you set your alerts and what you do with them, will be up to you. But generally speaking, once you get an alert, you should start weighing that pet even more than once a week to better help you determine the weight trend. But common sense must also prevail. If your pet is showing other symptoms of poor health, in addition to a drop in weight, get your pet to a vet!
A Moving Average with a Twist
While there may be some more sophisticated algorithm that could be used to calculate the baseline, we need one that not only works, but is easy to understand and easy to prove. So, the care chart uses a simple moving average calculation. Assuming that you weigh your pet every week, then a 14-day moving average (our default) will give you an average of the last three weight points over 14 days. We don't just take the weight points as hard numbers in determining the average. The average daily change between weight dates is determined and applied to get a more accurate average.
The Twist is that we do not allow DROPS in weight to be averaged into the baseline. If we did this, we would be suppressing the information of negative weight trends. So, we are very conservative in our approach to establishing a baseline for monitoring. This means that when a NEW BASELINE HIGH is established, that baseline point cannot be changed except by a higher baseline point being calculated OR a BASELINE RESET flag entered by you for a particular date.
A small drop in weight from a previous baseline high point might still even be above the baseline or not enough of a loss to trigger an alert.
Baseline Resets and When to Use Them
If your pet has been growing steadily or has been hovering around the baseline for some time, you won't get any alerts. But when weight loss alerts happen and you know why they are happening, then you need to adjust the graphing and calculations so that you can stop getting the alerts. That is when you need to reset the baseline.
When you edit a weight point to flag the Baseline Reset, the application will leave the prior calculations alone and from that point forward use that date's weight as the new Baseline. So, as weights increase from that date, then the baseline will increase.
Use baseline resets for:
A senior pet whose weight has declined to a lower level.
A mother who has given birth and is no longer pregnant.
A sick pet who is being treated and has lost some weight, but it is being managed.
A pet who had surgery and has lost some weight and needs a new baseline established as they recover.