The coding instructions for section K0300 sound simple but may not be upon closer inspection. From the MDS 3.0 RAI Manual: “This item compares the resident’s weight in the current observation period with his or her weight at two snapshots in time:

• At a point closest to 30-days preceding the current weight.
• At a point closest to 180-days preceding the current weight.”

As an example, an assessment reference date (ARD) is 4/22/19. Consider the list of weights below for the resident:

The current weight in K0200B would be 142 pounds, taken on 04/16. This is because the instructions for this item say to use the most recent weight in the last 30 days. The weight used for the 30-day comparison in K0300 would be 150 pounds, taken on 03/19, because this is the weight closest to a point 30 days preceding the current weight.

In summary, we have a 30-day lookback period to obtain the current weight. When there is more than one weight in the lookback period, we use the one closest to the ARD without going past the ARD. Once the current weight is determined, we use the date of that weight to determine the point closest to 30 days prior. In this case, 03/18 was 30 days prior to the date of the current weight, and the weight on 3/19 was the point closest to that date. The same procedure is used to find the point closest to 180 days prior to the current weight.

The next step is to determine weight loss for 30 and 180 days. Since the procedures are identical, we will just calculate weight loss for 30 days. The instructions are: “Start with the resident’s weight closest to 30 days ago and multiply it by 0.95 (or 95%). The resulting figure represents a 5% loss from the weight 30 days ago.” In our example, the calculation would be: 150 x 0.95 = 142.5. The current weight is less than 142.5, so the resident would have weight loss coded in K0300.

The final step is to review the chart to determine if the weight loss was planned and pursuant to a physician’s order, because we have two choices for coding weight loss based on whether it was or was not prescribed by a physician.