1) Individual dietary diversity is prone to seasonal differences. Do your best to collect baseline and endline data in the same period of a year; otherwise it is very likely that they will not be comparable. Do not collect data during the fasting periods (such as pre-Easter time or Ramadan) and during the fasting days.
2) This indicator relies on an accurate age assessment. Since people often do not remember the exact dates of their children’s birth, the data collectors should always verify the child’s age. This can be done by reviewing the child’s birth certificate, vaccination card or another document; however, since many caregivers do not have such documents (and since they can include mistakes), it is essential that your data collectors are able to verify the child’s age by using local events calendars. Read FAO’s Guidelines (see below) to learn how to prepare local events calendars and how to train data collectors in their correct use.
3) IDDS works with 8 food groups for children 6-23 months of age, and 9 food groups for children 24-59 months of age, older children and adults - for details, see WHO guidance below. Note that the original WHO 2010 guidance provided below works with 7 food groups for children 6-23 months of age; however, based on a June 2017 expert consultation it has been updated to reflect the inclusion of breast milk as an 8th food group. For details regarding this change, see WHO/UNICEF (2017) Operational Guidance provided in the documents below.
4) Record food groups in the questionnaire only after all meals were listed in the Recording Meals Form – never record it straightaway as it is very likely that the number of food groups consumed will be under-reported.
5) When training your data collectors, practice extensively which meals belong to which food group (allocate at least 3 hours full of examples and exercises). For example, while pumpkin flesh belongs to Vitamin A Rich Foods, pumpkin leaves belong to Dark Green Leafy Vegetables (see more examples in the FAO Guidelines below). If your questionnaire includes examples of different foods per each group, adjust them to the local context.
6) Do not record foods in quantities lower than one tea spoon (for example, a small amount of fish powder added for flavouring).
7) Well-designed, long-term (3 years or more) projects have a chance to increase the average IDDS by 1 score; for short-term projects, an increase by 0.5 score is a realistic maximum you can achieve.
8) Based on the number of meals included in the Recording Meals Form, you can also assess the meal frequency. Combination of IDDS + meal frequency data enables you to determine the percentage of children which consume a Minimum Acceptable Diet (see separate page on MAD indicator).
9) Take advantage of the very useful guidelines written by FAO and WHO - access below.