The Demographic and Health Surveys (DHS) Program has collected
population survey data from over 90 countries for over 30 years. In many
countries, DHS provide the key data that mark progress towards targets
such as the Sustainable Development Goals (SDGs) and inform health
policy. Though standard health indicators are routinely published in
survey final reports, much of the value of DHS is derived from the
ability to download and analyse standardized microdata datasets for
subgroup analysis, pooled multi-country analysis, and extended research
studies. The suite of tools within rdhs
improves the accessibility of
these datasets for statistical analysis with R, with aim to support
reproducible global health research and simplify common analytical
pipelines.
For questions regarding how to analyse DHS survey data, please read the DHS website’s data section first. If you have any questions after this then please create an issue with your question. It is really likely that your question will help other people and so posting them publically as an issue may help others with similar questions.
rdhs
is a package for management and analysis of Demographic and
Health Survey (DHS) data. This includes
functionality to:
- Access standard indicator data (i.e. DHS STATcompiler) in R via the DHS API.
- Identify surveys and datasets relevant to a particular analysis.
- Download survey datasets from the DHS website.
- Load datasets and associated metadata into R.
- Extract variables and combining datasets for pooled multi-survey analyses.
You can install the latest version from
CRAN
using:
install.packages("rdhs")
You can also install the development version of rdhs
with the latest
patches from github with:
#install.packages("devtools")
devtools::install_github("ropensci/rdhs")
# Load the package
library(rdhs)
To be able to download survey datasets from the DHS website, you
will need to set up an account with the DHS website, which will
enable you to request access to the datasets. Instructions on how to do
this can be found
here. The email,
password, and project name that were used to create the account will
then need to be provided to rdhs
when attempting to download datasets.
-
Request dataset access from the DHS website here.
-
Full functionality is described in the tutorial here.
-
An example workflow using
rdhs
to calculate trends in anemia prevalence is available here.
Query the DHS API.
Obtain survey estimates for Malaria prevalence among children from the Democratic Republic of Congo and Tanzania in the last 5 years (since 2013) that included rapid diagnostic tests (RDTs).
dhs_indicators(indicatorIds = "ML_PMAL_C_RDT", returnFields=c("IndicatorId", "ShortName"))
#> ShortName IndicatorId
#> 1 Malaria prevalence according to RDT ML_PMAL_C_RDT
dhs_data(countryIds = c("CD","TZ"), indicatorIds = "ML_PMAL_C_RDT", surveyYearStart = 2013,
returnFields=c("Indicator", "SurveyId", "Value", "SurveyYearLabel", "CountryName"))
#> Indicator SurveyId SurveyYearLabel Value
#> 1 Malaria prevalence according to RDT CD2013DHS 2013-14 30.8
#> 2 Malaria prevalence according to RDT TZ2015DHS 2015-16 14.4
#> 3 Malaria prevalence according to RDT TZ2017MIS 2017 7.3
#> CountryName
#> 1 Congo Democratic Republic
#> 2 Tanzania
#> 3 Tanzania
Now, obtain survey microdatasets to analyze these same indicators. Query the surveyCharacteristics endpoint to identify the survey characteristic ID for malaria RDT testing.
## call with no arguments to return all characterstics
sc <- dhs_survey_characteristics()
sc[grepl("Malaria", sc$SurveyCharacteristicName), ]
#> SurveyCharacteristicID SurveyCharacteristicName
#> 58 96 Malaria - DBS
#> 59 90 Malaria - Microscopy
#> 60 89 Malaria - RDT
#> 61 57 Malaria bednet inventory
Use dhs_surveys()
identify surveys for the countries and years of
interest.
## what are the countryIds - we can find that using this API request
ids <- dhs_countries(returnFields=c("CountryName", "DHS_CountryCode"))
## find all the surveys that match the search criteria
survs <- dhs_surveys(surveyCharacteristicIds = 89, countryIds = c("CD","TZ"), surveyYearStart = 2013)
Lastly, identify the datasets required for download. By default, the
recommended option is to download either the spss (.sav), fileFormat = "SV"
, or the flat file (.dat), fileFormat = "FL"
datasets. The flat
is quicker, but there are still one or two very old datasets that don’t
read correctly, whereas the .sav files are slower to read in but so far
no datasets have been found that don’t read in correctly. The household
member recode (PR
) reports the RDT status for children under
five.
datasets <- dhs_datasets(surveyIds = survs$SurveyId, fileFormat = "FL", fileType = "PR")
str(datasets)
#> 'data.frame': 3 obs. of 13 variables:
#> $ FileFormat : chr "Flat ASCII data (.dat)" "Flat ASCII data (.dat)" "Flat ASCII data (.dat)"
#> $ FileSize : int 6595349 6491292 2171918
#> $ DatasetType : chr "Survey Datasets" "Survey Datasets" "Survey Datasets"
#> $ SurveyNum : int 421 485 529
#> $ SurveyId : chr "CD2013DHS" "TZ2015DHS" "TZ2017MIS"
#> $ FileType : chr "Household Member Recode" "Household Member Recode" "Household Member Recode"
#> $ FileDateLastModified: chr "September, 19 2016 09:58:23" "September, 28 2019 17:58:28" "June, 11 2019 15:38:22"
#> $ SurveyType : chr "DHS" "DHS" "MIS"
#> $ SurveyYearLabel : chr "2013-14" "2015-16" "2017"
#> $ SurveyYear : chr "2013" "2015" "2017"
#> $ DHS_CountryCode : chr "CD" "TZ" "TZ"
#> $ FileName : chr "CDPR61FL.ZIP" "TZPR7BFL.ZIP" "TZPR7IFL.ZIP"
#> $ CountryName : chr "Congo Democratic Republic" "Tanzania" "Tanzania"
We can now go ahead and download our datasets. To be able to download
survey datasets from the DHS website, you will need to set up an account
with them to enable you to request access to the datasets. Instructions
on how to do this can be found
here. The email,
password, and project name that were used to create the account will
then need to be provided to rdhs
when attempting to download datasets.
Once we have created an account, we need to set up our credentials using
the function set_rdhs_config()
. This will require providing as
arguments your email
and project
for which you want to download
datasets from. You will then be prompted for your password.
You can also specify a directory for datasets and API calls to be cached
to using cache_path
. In order to comply with CRAN, this function will
also ask you for your permission to write to files outside your
temporary directory, and you must type out the filename for the
config_path
- “rdhs.json”. (See introduction
vignette for
specific format for config, or ?set_rdhs_config
).
## login
set_rdhs_config(email = "rdhs.tester@gmail.com",
project = "rdhs R package development",
config_path = "rdhs.json",
global = FALSE)
#> Writing your configuration to:
#> -> rdhs.json
The path to your config is saved between sessions so you only have to
set this once. With your credentials set, all API requests will be
cached within the cache_path
directory provided so that these can be
returned when working remotely or with a poor internet connection.
# the first time this will take a few seconds
microbenchmark::microbenchmark(dhs_datasets(surveyYearStart = 1986),times = 1)
#> Unit: milliseconds
#> expr min lq mean median uq
#> dhs_datasets(surveyYearStart = 1986) 46.3744 46.3744 46.3744 46.3744 46.3744
#> max neval
#> 46.3744 1
# after caching, results will be available instantly
microbenchmark::microbenchmark(dhs_datasets(surveyYearStart = 1986),times = 1)
#> Unit: milliseconds
#> expr min lq mean median
#> dhs_datasets(surveyYearStart = 1986) 1.410894 1.410894 1.410894 1.410894
#> uq max neval
#> 1.410894 1.410894 1
Now download datasets by providing a list of desired dataset filenames.
# download datasets
downloads <- get_datasets(datasets$FileName)
str(downloads)
#> List of 3
#> $ CDPR61FL: chr "/home/oj/.cache/rdhs/datasets/CDPR61FL.rds"
#> $ TZPR7BFL: chr "/home/oj/.cache/rdhs/datasets/TZPR7BFL.rds"
#> $ TZPR7IFL: chr "/home/oj/.cache/rdhs/datasets/TZPR7IFL.rds"
#> - attr(*, "reformat")= logi FALSE
The get_datasets()
function returns a vector with a file path to the
saved location of the downloaded datasets. These are read using
readRDS()
:
# read in first dataset
cdpr <- readRDS(downloads$CDPR61FL)
Value labels are stored as attributes to each of the columns of the data
frame using the labelled
class (see haven::labelled
or our
introduction vignette for more details). Variable labels are stored in
the label
attribute.
The client also caches all variable labels to quickly query variables in each survey without loading the datasets.
# rapid diagnostic test search
vars <- search_variable_labels(datasets$FileName, search_terms = "malaria rapid test")
Then extract these variables from the datasets. Optionally, geographic data may be added.
# and now extract the data
extract <- extract_dhs(vars, add_geo = FALSE)
#> Starting Survey 1 out of 3 surveys:CDPR61FL
#> Starting Survey 2 out of 3 surveys:TZPR7BFL
#> Starting Survey 3 out of 3 surveys:TZPR7IFL
The returned object is a list of extracted datasets.
Dataset extracts can alternate be specified by providing a vector of surveys and vector of variable names:
# and grab the questions from this now utilising the survey variables
vars <- search_variables(datasets$FileName, variables = c("hv024","hml35"))
# and now extract the data
extract <- extract_dhs(vars, add_geo = FALSE)
#> Starting Survey 1 out of 3 surveys:CDPR61FL
#> Starting Survey 2 out of 3 surveys:TZPR7BFL
#> Starting Survey 3 out of 3 surveys:TZPR7IFL
Finally, the two datasets are pooled using the function
rbind_labelled()
. This function works specifically with our lists of
labelled data.frame
s. Labels are specified for each variable: for
hv024
all labels are retained (concatenate) but for hml35
labels
across both datasets to be “Neg” and “Pos”.
# now let's try our second extraction
extract <- rbind_labelled(extract,
labels = list("hv024" = "concatenate",
"hml35" = c("Neg"=0, "Pos"=1)))
There is also an option to process downloaded datasets with labelled
variables coded as strings, rather than labelled variables. This is
specified by the argument reformat=TRUE
.
# identify questions but specifying the reformat argument
questions <- search_variables(datasets$FileName, variables = c("hv024", "hml35"),
reformat=TRUE)
# and now extract the data
extract <- extract_dhs(questions, add_geo = FALSE)
#> Starting Survey 1 out of 3 surveys:CDPR61FL
#> Starting Survey 2 out of 3 surveys:TZPR7BFL
#> Starting Survey 3 out of 3 surveys:TZPR7IFL
# group our results
extract <- rbind_labelled(extract)
# our hv024 variable is now just character strings, so you can decide when/how to factor/label it later
str(extract)
#> Classes 'dhs_dataset' and 'data.frame': 208595 obs. of 4 variables:
#> $ hv024 : chr "equateur" "equateur" "equateur" "equateur" ...
#> ..- attr(*, "label")= chr "Province"
#> $ hml35 : chr NA NA NA NA ...
#> ..- attr(*, "label")= chr "Result of malaria rapid test"
#> $ SurveyId: chr "CD2013DHS" "CD2013DHS" "CD2013DHS" "CD2013DHS" ...
#> $ DATASET : chr "CDPR61FL" "CDPR61FL" "CDPR61FL" "CDPR61FL" ...