Directions and scoring
Directions for Use: The time interval used in the directions can be adjusted to reflect your study design. For example, if your follow-up is 3 months, ask patients to “think about how you have been feeling in the last 3 months”. We recommend that no longer than 3 months be used, though, because of issues with recall.
Scoring: Previously we advocated use of a total score but we now strongly recommend that the 3 scales (self-care maintenance, management, and confidence) be used separately. Self-care is best represented by maintenance and management. Confidence is an important process that probably moderates the relationship between self-care and outcomes. This change benefits users because now even asymptomatic patients will have self-care maintenance and confidence scores. Self-care management scores remain appropriate only in persons who have been symptomatic. Specific formulas for calculating scale scores are available in the 2009 article.
Maintenance. To calculate the Maintenance scale scores, each scale score is standardized to a 0 to 100 range. There is one negatively worded item in the maintenance scale (# 8). After reverse-coding that item, standardize the raw score to a 0-100 scale. Note that more than half of the items in this section A should be answered for the scale to be an adequate measure of self-care maintenance.
Management. Score the management scale only if the patient reported having trouble breathing or ankle swelling in the past interval. Otherwise, ignore responses, even if the patient answers the items. Note that the first item (In the past month, have you had trouble breathing or ankle swelling?) is used only for this purpose and not in the scale score. Note that at least 2 of the 4 possible remedies must be answered for the scale to be an adequate measure of self-care management.
Confidence. Self-care confidence scores (Section C) should be standardized as described above. Note that more than half of the items in this section should be answered for the scale to be an adequate measure of self-care confidence.
SPSS Syntax for Scoring the SCHFI:
Here is some useful SPSS syntax for the SCHFIv6 (22 items). We are using different names and labels for these items. I just wrote the item numbers so that you can search and replace these with your own labels (e.g. first question = SCHFI1).
Please make sure that missing values (often written as 9, -9, or 99) are correctly specified in SPSS. Otherwise, you will be likely to have some high (>100) or low (<0) scores. Also, scores for subjects with missing data have to be calculated separately, depending on how many and which items they missed.
First, recode item #8.
RECODE SCHFI8 (1=4) (2=3) (3=2) (4=1).
Second, compute the Maintenance score.
Third, select patients who responded “yes”/1 to the first question under section B, and compute the Management score; be sure to replace “BreathAnkl” with your variable name.
IF (BreathAnkl=1) SCHFIManagement=(SUM(SCHFI11,SCHFI12,SCHFI13,SCHFI14,SCHFI15, SCHFI16)-4)*5.
Fourth, compute the Confidence score.