The DHS Program User Forum
Discussions regarding The DHS Program data and results
Home » Countries » Ethiopia » Problem with dates in the Ethiopia datasets
Re: Problem with dates in the Ethiopia datasets [message #67 is a reply to message #66] Wed, 20 February 2013 11:28 Go to previous messageGo to previous message
Bridgette-DHS is currently offline  Bridgette-DHS
Messages: 2345
Registered: February 2013
Senior Member
All standard date variables in the Ethiopia data file are in the Ethiopian calendar. In general the Ethiopian calendar is 92 months behind the Gregorian (western) calendar. The Ethiopian year runs from September 11 through September 10 and has 12 months of 30 days and 1 months of 5 days. Thus it is only possible to transfer the Ethiopian calendar into the Gregorian calendar when the exact date (day, month and year) is available. Therefore, in the file you will find additional variables indicating the Gregorian dates if they could be established.

Note that all standard variables based on calendar dates and century month codes are given in the Ethiopian Calendar. In general, the Ethiopian year consists of 365 days, divided into 12 months of 30 days and one month of 5 days (6 days in a leap year). Ethiopia's new year falls on September 11and ends the following September 10 according to the Gregorian calendar. From September 11 to December 31, the Ethiopian year runs seven years behind the Gregorian year, thereafter, the difference is eight years. Since the exact day is not available for most dates, it is not possible to convert the dates exactly, but only approximate it to the month. There is a difference of 92 months between the two date systems. The 13th month of the Ethiopian calendar falls in September. Thus, to keep the higher precision available in the Ethiopian calendar, these were used for all standard recode variables where applicable. In general, dates in the Gregorian calendar are provided as country specific variables. However, the calendar is transferred to the Gregorian calendar.

To explain somewhat further, the number of months in the CMC variables (even for Ethiopian dates) are computed as follows: each year has 12 months, but when the event was in the 13th month then 13 is added for the number of months. Thus e.g. a person was born in the 13th month of 1960 in the Ethiopian calendar, then the CMC is 60 * 12 + 13. Thus the 5 days in the 13th month really go to the following year when you recomputed the CMC back to years (with 12 months). But this will cause little bias. So just use the CMC as you would for other surveys (intervals should not be divided by 13, but by 12). However, know that on average the Ethiopian calendar lags 92 months behind our Gregorian system.

The Ethiopian calendar was kept as the standard variables, sinceĀ  not all dates (e.g. vaccination dates) could be transferred.

Here is a link that you can use to convert Ethiopian dates:

http://www.funaba.org/en/calendar-conversion.cgi

Attached is a little Stata script: "ETcalconvert", that you may find useful (written by DHS Data User: Keith Kranker).

I hope this helps.

Bridgette-DHS

[Updated on: Mon, 18 March 2013 09:14]

Report message to a moderator

 
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: Height and Weight Scores (WHO Child Growth Standards) data
Next Topic: prevalence of anemia and associated factors
Goto Forum:
  


Current Time: Sat Jul 24 04:11:52 Coordinated Universal Time 2021