CEP-005: Sleep variables

Overview

This CEP documents the harmonization of sleep variables in cchsflow for the Canadian Community Health Survey (CCHS).

PR: #161 - Sleep variables

Status: Ready for merge

Sleep variables in scope

Variable Description Type Cycles
SLPG01 Hours sleep Categorical 2011+ PUMF
SLPG01_A Hours sleep Categorical 2001, 2007-2008 PUMF
SLPG01_B Hours sleep Categorical 2011-2014 Master
SLPG01_C Hours sleep Categorical 2001, 2015-2016 Master
SLPG01_cont Hours sleep Continuous All available cycles
SLP_02 Trouble sleeping Categorical 2007+ (5-point scale)
SLP_02_A Trouble sleeping Categorical 2001 (3-point scale)
SLP_03 Sleep refreshing Categorical 2007+ (5-point scale)
SLP_03_A Sleep refreshing Categorical 2001 (3-point scale)
SLP_04 Difficulty staying awake Categorical 2007+ (5-point scale)
SLP_04_A Difficulty staying awake Categorical 2001 (3-point scale)

Critical finding: Ontario sleep data gap

13-year gap confirmed

Ontario sleep data has a 13-year gap (2003-2014) in both PUMF and Ontario Linked/Share files. This was confirmed by three independent sources:

  1. PUMF direct analysis - .RData file validation
  2. GoogleLM cross-check - Statistics Canada documentation review
  3. ICES Dictionary v1.0.0 - 14,005 variable availability matrix

Ontario sleep data availability

Epoch Years PUMF ONT_LINK/SHARE Variables Scale
Early era 2001-2002 2001 only Both years GENA_03-06, GENB_03-05 3-point
Gap 2003-2014 None None Missing N/A
Modern era 2015-2018 2015-16 only Both years SLP_005, SLP_010-020 5-point

Why the gap exists

  • Sleep was Optional Content from 2007-2018
  • Ontario did NOT select the sleep module for 2007-2014 and 2017-2018
  • Ontario DID select the sleep module for 2015-2016 only
  • This applies to both PUMF and Master/Linked files

Cycles without sleep data (Canada-wide PUMF)

Sleep variables are NOT available in the following PUMF cycles for any province:

  • 2003
  • 2005
  • 2009-2010

This was verified via DDI XML review.

Scale incompatibility

The sleep quality variables have incompatible response scales between 2001 and 2007+:

Era Scale Response options Direction
2001 3-point Most of the time / Sometimes / Never Lower = worse
2007+ 5-point None / A little / Some / Most / All Higher = worse
Scales are inverted

2001: 1 = “Most of the time” (worst) 2007+: 1 = “None of the time” (best)

Do not pool 2001 with 2007+ data without careful harmonization.

Harmonization recommendation

Create binary variable “Any trouble sleeping”: - 2001: 1 & 2 (“Most” + “Sometimes”) = Yes; 3 (“Never”) = No - 2007+: 2-5 (“A little” to “All”) = Yes; 1 (“None”) = No

Variable naming evolution

Era Hours Trouble Refreshing Awake
2001 GENA_03 GENA_04 GENA_05 GENA_06
2002 GENB_03 GENB_04 GENB_05 Not found
2007-2008 SLP_01 SLP_02 SLP_03 SLP_04
2011-2014 SLPG01 SLP_02 SLP_03 SLP_04
2015-2018 SLPG005 SLP_010 SLP_015 SLP_020

Documents

Recommendations for Ontario dementia research

PUMF analysis

Cycle Ontario sleep data Notes
2001 Available 3-point scale (~9,400 Ontario 50+)
2003 Not in PUMF Canada-wide exclusion
2005 Not in PUMF Canada-wide exclusion
2007-2008 NOT available Ontario excluded from optional module
2009-2010 Not in PUMF Canada-wide exclusion
2011-2012 NOT available Ontario excluded from optional module
2013-2014 NOT available Ontario excluded from optional module
2015-2016 Available 5-point scale (~14,400 Ontario 50+)
2017-2018 NOT available Ontario excluded from optional module

ICES Linked/Share file analysis

Cycle Ontario sleep data Dataset
2001 Available CCHS2001_ONT_LINK_11
2002 Available CCHS2002_ONT_LINK_12
2003-2014 NOT available N/A
2015-2016 Available CCHS201516_ONT_SHARE
2017-2018 Available CCHS201718_ONT_SHARE
ICES advantage

ICES Linked/Share files provide 2002 and 2017-2018 Ontario sleep data not available in PUMF.