ALGAE Data Dictionary: Early life exposures, using uncleaned mobility assessment

An automated protocol for assigning early life exposures to longitudinal cohort studies

ALGAE Data Dictionary: Early life exposures, using uncleaned mobility assessment (algae3200-algae3242)

by Kevin Garwood

Context of Variables

These pollution exposures for the early life analysis have been produced using the uncleaned mobility assessment.

Using this method, exposure contributions are considered for all address periods that overlap with the overall exposure time frame (eg: conception date to last day of first year of life). However, days of contention are omitted from cumulative, average and median calculations. Note that in the case of average calculations, the days are omitted from both the numerator showing a cumulative exposure and from the denominator which indicates the total days in a life stage.

For each study member, cumulative, average and median exposures are assessed based on two factors:

For each life stage, the protocol counts the number of days which can be described by the following categories for data quality:

Please see the Assess the Data Quality of Each Daily Exposure Value section of the ALGAE methodology to learn more about these data quality categories.

Variables marked _err aggregate daily exposure errors for a given pollutant and life stage.

Location of Result File

You will find these variables in a file having a name that fits the form: 
res_early_mob_uncln_exp_[Date stamp].csv
which will be found in the directory: 
early_life/results/exposure_data/mobility_unclean
or 
later_life/results/exposure_data/mobility_unclean

Example Result File

See here.

Variable Naming Conventions

It may be quicker to understand the variables through naming conventions rather than looking at specific table entries. The basic format of variables in this section follows this pattern: 
	algae32[0-16]_[pollution type]_[aggregate value]

In this pattern:

  • algae32: indicates that they refer to exposure values for early life that ignore days that are involved in gaps or overlaps.
  • pollution_type: will be name, nox_rd, pm10_tot, pm10_rd, pm10_gr
  • aggregate value: sum for cumulative value, avg for average value and med for median value.

The pollutant codes have the following meanings:

  • name: high level pollution that comes from outside the exposure area
  • nox_rd: Nitrogen oxide pollution coming from roads
  • pm10_rd: PM10 particulate matter coming from roads.
  • pm10_gr: PM10 particulate matter coming from sources other than roads.
  • pm10_tot: PM10 particulate matter coming from either roads or other sources.

Variable Dictionary

Variable Description
algae3200_person_id An anonymised or pseudonymised identifier which represents a study member. ALGAE uses this variable to link data together for a given study member.
algae3201_life_stage The name of a life stage. For example, "T1" may be the name of the Trimester 1 life stage.
algae3202_life_stage_duration The number of days in the life stage.
algae3203_name_inv_addr_days The number of NAME exposure days in the life stage that the study member spent at an invalid address. See definition of Invalid address days.
algae3204_name_oob_days The number of NAME exposure days in the life stage that the study member spent living at a location that is considered outside the bounds of the exposure area. See definition of Out of bounds days.
algae3205_name_poor_addr_days The number of NAME exposure days in the life stage that the study member spent living at a location whose geocode was derived from a poor quality residential address. The geocode was used to generate exposure values, but it is still considered to be invalid because it is of such poor quality. See definition of Poor address days.
algae3206_name_missing_exp_days The number of NAME exposure days in the life stage that the study member spent living at a valid geocode which has some exposure values but not for specific days. See definition of Missing exposure days.
algae3207_name_good_addr_days The number of NAME exposure days in the life stage that the study member spent living at a geocode that is considered a good match: it has a valid geocode and it has a non-blank exposure value for a given day. See definition of Good address days.
algae3208_nox_rd_inv_addr_days The number of NOX RD exposure days in the life stage that the study member spent at an invalid address. See definition of Invalid address days.
algae3209_nox_rd_oob_days The number of NOX RD exposure days in the life stage that the study member spent living at a location that is considered outside the bounds of the exposure area. See definition of Out of bounds days.
algae3210_nox_rd_poor_addr_days The number of NOX RD exposure days in the life stage that the study member spent living at a location whose geocode was derived from a poor quality residential address. The geocode was used to generate exposure values, but it is still considered to be invalid because it is of such poor quality. See definition of Poor address days.
algae3211_nox_rd_missing_exp_days The number of NOX RD exposure days in the life stage that the study member spent living at a valid geocode which has some exposure values but not for specific days. See definition of Missing exposure days.
algae3212_nox_rd_good_addr_days The number of NOX RD exposure days in the life stage that the study member spent living at a geocode that is considered a good match: it has a valid geocode and it has a non-blank exposure value for a given day. See definition of Good address days.
algae3213_pm10_rd_inv_addr_days The number of PM10 RD exposure days in the life stage that the study member spent at an invalid address. See definition of Invalid address days.
algae3214_pm10_rd_oob_days The number of PM10 RD exposure days in the life stage that the study member spent living at a location that is considered outside the bounds of the exposure area. See definition of Out of bounds days.
algae3215_pm10_rd_poor_addr_days The number of PM10 RD exposure days in the life stage that the study member spent living at a location whose geocode was derived from a poor quality residential address. The geocode was used to generate exposure values, but it is still considered to be invalid because it is of such poor quality. See definition of Poor address days.
algae3216_pm10_rd_missing_exp_days The number of PM10 RD exposure days in the life stage that the study member spent living at a valid geocode which has some exposure values but not for specific days. See definition of Missing exposure days.
algae3217_pm10_rd_good_addr_days The number of PM10 RD exposure days in the life stage that the study member spent living at a geocode that is considered a good match: it has a valid geocode and it has a non-blank exposure value for a given day. See definition of Good address days.
algae3218_pm10_gr_inv_addr_days The number of PM10 GR exposure days in the life stage that the study member spent at an invalid address. See definition of Invalid address days.
algae3219_pm10_gr_oob_days The number of PM10 GR exposure days in the life stage that the study member spent living at a location that is considered outside the bounds of the exposure area. See definition of Out of bounds days.
algae3220_pm10_gr_poor_addr_days The number of PM10 GR exposure days in the life stage that the study member spent living at a location whose geocode was derived from a poor quality residential address. The geocode was used to generate exposure values, but it is still considered to be invalid because it is of such poor quality. See definition of Poor address days.
algae3221_pm10_gr_missing_exp_days The number of PM10 GR exposure days in the life stage that the study member spent living at a valid geocode which has some exposure values but not for specific days. See definition of Missing exposure days.
algae3222_pm10_gr_good_addr_days The number of PM10 GR exposure days in the life stage that the study member spent living at a geocode that is considered a good match: it has a valid geocode and it has a non-blank exposure value for a given day. See definition of Good address days.
algae3223_pm10_tot_inv_addr_days The number of PM10 TOT exposure days in the life stage that the study member spent at an invalid address. See definition of Invalid address days.
algae3224_pm10_tot_oob_days The number of PM10 TOT exposure days in the life stage that the study member spent living at a location that is considered outside the bounds of the exposure area. See definition of Out of bounds days.
algae3225_pm10_tot_poor_addr_days The number of PM10 TOT exposure days in the life stage that the study member spent living at a location whose geocode was derived from a poor quality residential address. The geocode was used to generate exposure values, but it is still considered to be invalid because it is of such poor quality. See definition of Poor address days.
algae3226_pm10_tot_missing_exp_days The number of PM10 TOT exposure days in the life stage that the study member spent living at a valid geocode which has some exposure values but not for specific days. See definition of Missing exposure days.
algae3227_pm10_tot_good_addr_days The number of PM10 TOT exposure days in the life stage that the study member spent living at a geocode that is considered a good match: it has a valid geocode and it has a non-blank exposure value for a given day. See definition of Good address days.
algae3228_name_sum Cumulative exposure of NAME for the given life_stage.
algae3229_name_avg Average exposure for NAME measured for the given life_stage
algae3230_name_med Median exposure for NAME measured for the given life_stage
algae3231_nox_rd_sum Cumulative exposure of NOX (road sources) for a given life_stage.
algae3232_nox_rd_avg Average exposure of NOX (road sources) for a given life_stage.
algae3233_nox_rd_med Median exposure for NOX (road sources), measured for the given life_stage
algae3234_pm10_gr_sum Cumulative exposure for PM10 (non-road sources), measured for the given life_stage
algae3235_pm10_gr_avg Average exposure for PM10 (non-road sources), measured for the given life_stage
algae3236_pm10_gr_med Median exposure for PM10 (non-road sources), measured for the given life_stage
algae3237_pm10_rd_sum Cumulative exposure for PM10 (road sources), measured for the given life_stage
algae3238_pm10_rd_avg Average exposure for PM10 (road sources), measured for the given life_stage
algae3239_pm10_rd_med Median exposure for PM10 (road sources), measured for the given life_stage
algae3240_pm10_tot_sum Cumulative exposure for PM10 (all sources), measured for the given life_stage
algae3241_pm10_tot_avg Average exposure for PM10 (all sources), measured for the given life_stage
algae3242_pm10_tot_med Median exposure for PM10 (all sources), measured for the given life_stage