DOI: 10.3886/icpsr36498.v23
title: Population Assessment of Tobacco and Health (PATH) Study [United States] Public-Use Files
title: Version 23

description: The Population Assessment of Tobacco and Health (PATH) Study began originally surveying 45,971 adult and youth respondents. The PATH Study was launched in 2011 to inform Food and Drug Administration's regulatory activities under the Family Smoking Prevention and Tobacco Control Act (TCA). The PATH Study is a collaboration between the National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH), and the Center for Tobacco Products (CTP), Food and Drug Administration (FDA). The study sampled over 150,000 mailing addresses across the United States to create a national sample of people who use or do not use tobacco.
45,971 adults and youth constitute the first (baseline) wave of data collected by this longitudinal cohort study. These 45,971 adults and youth along with 7,207 "shadow youth" (youth ages 9 to 11 sampled at Wave 1) make up the 53,178 participants that constitute the Wave 1 Cohort. Respondents are asked to complete an interview at each follow-up wave. Youth who turn 18 by the current wave of data collection are considered "aged-up adults" and are invited to complete the Adult Interview. Additionally, "shadow youth" are considered "aged-up youth" upon turning 12 years old, when they are asked to complete an interview after parental consent.
At Wave 4, a probability sample of 14,098 adults, youth, and shadow youth ages 10 to 11 was selected from the civilian, noninstitutionalized population at the time of Wave 4. This sample was recruited from residential addresses not selected for Wave 1 in the same sampled Primary Sampling Unit (PSU)s and segments using similar within-household sampling procedures. This "replenishment sample" was combined for estimation and analysis purposes with Wave 4 adult and youth respondents from the Wave 1 Cohort who were in the civilian, noninstitutionalized population at the time of Wave 4. This combined set of Wave 4 participants, 52,731 participants in total, forms the Wave 4 Cohort.Dataset 0001 (DS0001) contains the data from the Master Linkage file. This file contains 14 variables and 67,276 cases. The file provides a master list of every person's unique identification number and what type of respondent they were for each wave.
At Wave 7, a probability sample of 14,863 adults, youth, and shadow youth ages 9 to 11 was selected from the civilian, noninstitutionalized population at the time of Wave 7. This sample was recruited from residential addresses not selected for Wave 1 or Wave 4 in the same sampled PSUs and segments using similar within-household sampling procedures. This second replenishment sample was combined for estimation and analysis purposes with Wave 7 adult and youth respondents from the Wave 4 Cohort who were at least age 15 and in the civilian, noninstitutionalized population at the time of Wave 7. This combined set of Wave 7 participants, 46,169 participants in total, forms the Wave 7 Cohort.
Please refer to the Public-Use Files User Guide that provides further details about children designated as "shadow youth" and the formation of the Wave 1, Wave 4, and Wave 7 Cohorts.Dataset 1001 (DS1001) contains the data from the Wave 1 Adult Questionnaire. This data file contains 1,732 variables and 32,320 cases. Each of the cases represents a single, completed interview.
Dataset 1002 (DS1002) contains the data from the Youth and Parent Questionnaire. This file contains 1,228 variables and 13,651 cases.Dataset 2001 (DS2001) contains the data from the Wave 2 Adult Questionnaire. This data file contains 2,197 variables and 28,362 cases. Of these cases, 26,447 also completed a Wave 1 Adult Questionnaire. The other 1,915 cases are "aged-up adults" having previously completed a Wave 1 Youth Questionnaire.
Dataset 2002 (DS2002) contains the data from the Wave 2 Youth and Parent Questionnaire. This data file contains 1,389 variables and 12,172 cases. Of these cases, 10,081 also completed a Wave 1 Youth Questionnaire. The other 2,091 cases are "aged-up youth" having previously been sampled as "shadow youth."
Dataset 3001 (DS3001) contains the data from the Wave 3 Adult Questionnaire. This data file contains 2,139 variables and 28,148 cases. Of these cases, 26,241 are continuing adults having completed a prior Adult Questionnaire. The other 1,907 cases are "aged-up adults" having previously completed a Youth Questionnaire.
Dataset 3002 (DS3002) contains the data from the Wave 3 Youth and Parent Questionnaire. This data file contains 1,309 variables and 11,814 cases. Of these cases, 9,769 are continuing youth having completed a prior Youth Interview. The other 2,045 cases are "aged-up youth" having previously been sampled as "shadow youth."
Datasets 3101, 3102, 3201 and 3202 (DS3101, DS3102, DS3201, and DS3202) are data files comprising the weight variables for Wave 3. The weight variables for Wave 1 and Wave 2 are included in the main data files. However, in Wave 3, the weight variables have been separated into individual data files for Adult and Youth Questionnaires. The "all-waves" weight files contain weights for those respondents who have completed an interview during all three waves of data collection. The "single-wave" weight files contain weights for all respondents in Wave 3 regardless of their participation in previous waves.
Dataset 3503 (DS3503) contains data derived from responses to Wave 1-3 questionnaires indicating if participants had ever/never used various tobacco products as of the Wave 3 study period. This data file contains 25 variables for all 53,178 study participants as of Wave 3. This file is provided for reference only to simplify the definitions of tobacco use variables in the Adult and Youth data files for subsequent waves.
Dataset 4001 (DS4001) contains the data from the Wave 4 Adult Questionnaire. This data file contains 2,182 variables and 33,822 cases. Of these cases, 25,857 are continuing adults having completed a prior Adult Questionnaire, 1,900 are "aged-up adults" having previously completed a Youth Questionnaire, and 6,065 are "replenishment sample adults" (also known as "new cohort adults" in the annotated instrument).
Dataset 4002 (DS4002) contains the data from the Wave 4 Youth and Parent Questionnaire. This data file contains 1,389 variables and 14,798 cases. Of these cases, 9,365 are continuing youth having completed a prior Youth Interview, 1,694 cases are "aged-up youth" having previously been sampled as "shadow youth," and 3,739 are "replenishment sample youth" (also known as "new cohort youth" in the annotated instrument).
Datasets 4111, 4112, 4211, 4212, 4321, and 4322 (DS4111, DS4112, DS4211, DS4212, DS4321, and DS4322) are data files comprising the weight variables for Wave 4. In Wave 4, the weight variables have been separated into individual data files corresponding to the Wave 1 and Wave 4 Cohorts and different weight types. The "all-waves" weight files contain weights for those Wave 1 Cohort respondents who completed an interview for all waves in which they were old enough or verified their information for waves in which they were not old enough to be interviewed. The "single-wave" weight files contain weights for Wave 1 Cohort respondents at Wave 4 who completed an interview at Wave 1, regardless of their participation in previous waves. The "cross-sectional" weight files contain weights for all respondents in the Wave 4 Cohort.
Dataset 4503 (DS4503) contains data derived from responses to Wave 1-4 questionnaires indicating if participants had ever/never used various tobacco products as of the Wave 4 data collection period. This data file contains 27 variables for all 67,276 study participants as of the Wave 4 data collection. This file is provided for reference only to simplify the definitions of tobacco use variables in the Adult and Youth data files for subsequent waves.
Dataset 5001 (DS5001) contains the data from the Wave 5 Adult Questionnaire. This data file contains 2,315 variables and 34,309 cases. Of these cases, 29,876 are continuing adults having completed a prior Adult Questionnaire, 4,433 are "aged-up adults" having previously completed a Youth Questionnaire.Dataset 5002 (DS5002) contains the data from the Wave 5 Youth and Parent Questionnaire. This data file contains 1,530 variables and 12,098 cases. Of these cases, 10,446 are continuing youth having completed a prior Youth Interview, 1,652 cases are "aged-up youth" having previously been sampled as "shadow youth."Datasets 5111, 5112, 5211, 5212, 5221, 5222, 5711, 5712, 5721, and 5722 (DS5111, DS5112, DS5211, DS5212, DS5221, DS5222, DS5711, DS5712, DS5721, and DS5722) are data files comprising the weight variables for Wave 5. In Wave 5, the weight variables are in individual data files corresponding to the Wave 1 and Wave 4 Cohorts and different weight types. The "all-waves" weight files contain weights for those Wave 1 Cohort participants who completed a Wave 5 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, and 4.
Dataset 5503 (DS5503) contains data derived from responses to Wave 1-5 (including Wave 4.5) questionnaires indicating if participants had ever/never used various tobacco products as of the Wave 5 data collection period. This data file contains 26 variables for all 67,276 study participants as of the Wave 5 data collection. This file is provided for reference only to simplify the definitions of tobacco use variables in the Adult and Youth data files for subsequent waves.There are two separate sets of files with "single wave" weights: one for the Wave 1 Cohort and one for the Wave 4 Cohort. The "single-wave" weight files for the Wave 1 Cohort contain weights for participants who completed an interview in Wave 1 and in Wave 5, regardless of their participation in the intervening waves. The "single-wave" weight files for the Wave 4 Cohort contain weights for all Wave 5 interview respondents in the Wave 4 Cohort.There are also two separate sets of files with "special collection all-waves" weights: one for the Wave 1 Cohort and one for the Wave 4 Cohort. The "special collection all-waves" weight files for the Wave 1 Cohort contains weights for participants who completed a Wave 5 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, and the special collection in Wave 4.5. The "special collection all-waves" weight files for the Wave 4 Cohort contain weights for participants who completed a Wave 5 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Wave 4 and the special collection in Wave 4.5.
Dataset 6001 (DS6001) contains the data from the Wave 6 Adult
Questionnaire. This data file contains 2,589 variables and 30,516 cases. Of these cases, 28,852 are continuing adults having completed a prior Adult Questionnaire and 1,664 are "aged-up adults" having previously completed a Youth Questionnaire.Dataset 6002 (DS6002) contains the data from the Wave 6 Youth and Parent Questionnaire. This data file contains 1,822 variables and 5,652 cases. Of these cases, 5,622 are continuing youth having completed a prior Youth interview and 30 cases are "aged-up youth" having previously been sampled as "shadow youth."Datasets 6111, 6112, 6121, 6122, 6211, 6212, 6221, 6222, 6711, 6712, 6721, and 6722 (DS6111, DS6112, DS6121, DS6122, DS6211, DS6212, DS6221, DS6222, DS6711, DS6712, DS6721, and DS6722) are data files comprising the weight variables for Wave 6. In Wave 6, the weight variables are in individual data files corresponding to the Wave 1 and Wave 4 Cohorts and different weight types. There are two separate sets of files with "all-waves" weights: one for the Wave 1 Cohort and one for the Wave 4 Cohort. The "all-waves" weight files for the Wave 1 Cohort contain weights for participants who completed a Wave 6 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, and 5. The "all-waves" weight files for the Wave 4 Cohort contain weights for participants who completed a Wave 6 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 4 and 5.There are two separate sets of files with "single-wave" weights: one for the Wave 1 Cohort and one for the Wave 4 Cohort. The "single-wave" weight files for the Wave 1 Cohort contain weights for participants who completed an interview in Wave 1 and in Wave 6, regardless of their participation in the intervening waves. The "single-wave" weight files for the Wave 4 Cohort contain weights for participants who completed an interview in Wave 4 and in Wave 6, regardless of their participation in the intervening waves.There are also two separate sets of files with "special collection all-waves" weights: one for the Wave 1 Cohort and one for the Wave 4 Cohort. The "special collection all-waves" weight files for the Wave 1 Cohort contain weights for participants who completed a Wave 6 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, 5, and the special collections in Wave 4.5, and Wave 5.5 or PATH-ATS. The "special collection all-waves" weight files for the Wave 4 Cohort contain weights for participants who completed a Wave 6 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 4 and 5, and the special collections in Wave 4.5, and Wave 5.5 or PATH-ATS.Dataset 7001 (DS7001) contains the data from the Wave 7 Adult Questionnaire. This data file contains 2,813 variables and 30,801 cases. Of these cases, 27,258 are continuing adults having completed a prior Adult Questionnaire, 1,740 are "aged-up adults" having previously completed a Youth Questionnaire, and 1,803 are "replenishment sample adults" (also known as "new cohort adults" in the annotated instrument).Dataset 7002 (DS7002) contains the data from the Wave 7 Youth and Parent Questionnaire. This data file contains 1,897 variables and 10,834 cases. Of these cases, 3,512 are continuing youth having completed a prior Youth Interview, 1 case is an "aged-up youth" having previously been sampled as "shadow youth," and 7,321 are "replenishment sample youth" (also known as "new cohort youth" in the annotated instrument).Datasets 7111, 7112, 7121, 7122, 7211, 7212, 7221, 7222, 7331, 7332, 7711, 7712, 7721, and 7722 (DS DS7111, DS7112, DS7121, DS7122, DS7211, DS7212, DS7221, DS7222, DS7331, DS7332, DS7711, DS7712, DS7721, and DS7722) are data files comprising the weight variables for Wave 7. In Wave 7, the weight variables are in individual data files corresponding to the Wave 1, Wave 4, and Wave 7 Cohorts and different weight types.There are two separate sets of files with "all-waves" weights: one for the Wave 1 Cohort and one for the Wave 4 Cohort. The "all-waves" weight files for the Wave 1 Cohort contain weights for participants who completed a Wave 7 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, 5, and 6. The "all-waves" weight files for the Wave 4 Cohort contain weights for participants who completed a Wave 7 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 4, 5, and 6.There are two separate sets of files with "single-wave" weights: one for the Wave 1 Cohort and one for the Wave 4 Cohort. The "single-wave" weight files for the Wave 1 Cohort contain weights for participants who completed an interview in Wave 1 and in Wave 7, regardless of their participation in the intervening waves. The "single-wave" weight files for the Wave 4 Cohort contain weights for participants who completed an interview in Wave 4 and in Wave 7, regardless of their participation in the intervening waves.There are also two separate sets of files with "special collection all-waves" weights: one for the Wave 1 Cohort and one for the Wave 4 Cohort. The "special collection all-waves" weight files for the Wave 1 Cohort contain weights for participants who completed a Wave 7 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, 5, 6, and the special collections in Wave 4.5, and Wave 5.5 or PATH-ATS. The "special collection all-waves" weight files for the Wave 4 Cohort contain weights for participants who completed a Wave 7 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 4, 5, 6, and the special collections in Wave 4.5, and Wave 5.5 or PATH-ATS.The "cross-sectional" weight files contain weights for all respondents in the Wave 7 Cohort.
Dataset 6503 (DS6503) contains data derived from responses to Wave 1-6 (including Wave 4.5, Wave 5.5, and PATH-ATS) questionnaires indicating if participants had ever/never used various tobacco products as of the Wave 6 data collection period. This data file contains 24 variables for all 67,276 study participants as of the Wave 6 data collection. This file is provided for reference only to simplify the definitions of tobacco use variables in the Adult and Youth data files for subsequent waves.
Each case in an Adult data file represents a single, completed interview. Each case in a Youth data file represents one youth and his or her parent's responses about that youth. Parents who provided permission for their child to participate in a Youth Interview were asked to complete a brief interview about their child. Across all waves of data collection, an average of 0.6 percent of the parents did not complete an interview. Most questions are asked about the child.
When multiple youth from the same household were selected to be in the study, the parent(s) completed separate interviews about each youth. If one parent completed two or more interviews, that parent only answered questions about himself/herself once. Those questions were then skipped in the subsequent interview(s) for the other child(ren) and the responses duplicated in that child(ren)'s data file(s).
description: The Population Assessment of Tobacco and Health (PATH) Study is a nationally representative longitudinal cohort study on tobacco use behavior, attitudes and beliefs, and tobacco-related health outcomes among adults and youth in the United States. The study's primary objectives are to:


<strong>Objective 1:</strong> Identify and explain between-person differences and within-person changes in tobacco-use patterns, including the rate and length of use by specific product type and brand, product/brand switching over time, uptake of new products, and dual- and poly-use of tobacco products (i.e., use of multiple products within the same time period and switching between multiple products).
<strong>Objective 2:</strong> Identify between-person differences and within-person changes in risk perceptions regarding harmful and potentially harmful constituents, new and emerging tobacco products, filters and other design features of tobacco products, packaging, and labeling; and identify other factors that may affect use, such as social influences and individual preferences.
<strong>Objective 3:</strong> Characterize the natural history of tobacco dependence, cessation, and relapse, including readiness and self-efficacy to quit, motivations for quitting, the number and length of quit attempts, and the length of abstinence related to various tobacco products.
<strong>Objective 4:</strong> Update the comprehensive baseline and subsequent waves of data on tobacco-use behaviors and related health conditions, including markers of exposure and tobacco-related disease processes identified from the collection and analysis of biospecimens, to assess between-person differences and within-person changes over time in health conditions potentially related to tobacco use, particularly with use of new and different tobacco products, including modified-risk tobacco products.
<strong>Objective 5:</strong> Assess associations between TCA-specific actions and tobacco-product use, risk perceptions and attitudes, use patterns, cessation outcomes, and tobacco-related intermediate endpoints (e.g., biomarkers of exposure and biomarkers related to disease). Analyses will attempt to account for other potential factors, such as demographics, local tobacco-control policies, and social, familial, and economic factors, that may influence the observed patterns.
<strong>Objective 6:</strong> Assess between-person differences and within-person changes over time in attitudes, behaviors, exposure to tobacco products, and related biomarkers among and within population sub-groups identified by such characteristics as race-ethnicity, sex, and/or age, or by risk factors, such as pregnancy or co-occurring substance use or mental health disorders.
<strong>Objective 7:</strong> To the extent to which sample sizes are sufficient, assess and compare samples of those who report former and never use of tobacco products for between-person differences and within-person changes in relapse and uptake, risk perceptions, and indicators of tobacco exposure and disease processes.
<strong>Objective 8:</strong> Use data from the PATH Study's baseline and follow-up waves on tobacco-use behaviors, attitudes, and related health conditions, including potential markers of exposure and related disease processes identified from the analysis of biospecimens, to screen and subsample respondents for participation in formative and/or nested studies conducted during and after the PATH Study's waves of data and biospecimen collection.
description: At Wave 1, The study sampled over 150,000 mailing addresses which, using a four-staged stratified sampling design, yielded a sample of 45,971 respondents (32,320 adults / 13,651 youth) who completed a Wave 1 interview. People who use or do not use tobacco, who were at least 9 years old living in a civilian, non-institutionalized setting were considered for participation during Wave 1. Youth who turn 18 by the next wave of data collection are considered "aged-up adults" and are invited to complete the Adult Interview. Additionally, 7,207 "shadow youth" (youth ages 9 to 11 sampled at Wave 1) are considered "aged-up youth" upon turning 12 years old when they are asked to join the study. The 45,971 adults and youth along with 7,207 "shadow youth" make up the 53,178 participants that constitute the Wave 1 Cohort
At Wave 4, the Wave 1 Cohort was replenished with a probability sample of 14,098 adults, youth, and shadow youth ages 10 to 11 selected from the U.S. civilian, noninstitutionalized population (CNP) at the time of Wave 4. This sample was recruited from close to 174,000 mailing addresses not selected for Wave 1, in the same sampled PSUs and segments using similar within-household sampling procedures. To meet the needs for the Wave 4 Cohort shadow sample, a randomly selected subset of the sampled addresses (115,500 or close to two-thirds of the addresses) were screened solely to identify shadow youth ages 10 to 11. The remaining addresses (close to 58,500) were screened for adults, youth, and shadow youth ages 10 to 11. These are referred to as the "SO" (shadow youth only) and "AYS" (adults, youth, and shadow youth) replenishment samples, respectively. This replenishment sample was combined for estimation and analysis purposes with Wave 4 adult and youth respondents from the Wave 1 Cohort who were in the U.S. CNP at the time of Wave 4. This combined set of Wave 4 participants, 52,731 participants in total, forms the Wave 4 Cohort.At Wave 7, a probability sample of 14,863 adults, youth, and shadow youth ages 9 to 11 was selected from the civilian, noninstitutionalized population at the time of Wave 7. This sample was recruited from close to 244,000 mailing addresses not selected for Wave 1 or Wave 4, in the same sampled PSUs and segments using similar within-household sampling procedures. To meet the needs for the Wave 7 youth sample and the need for a Wave 7 Cohort shadow sample, the address sample was randomly divided into three subsamples. A subset of about 111,500 addresses (or close to 45 percent) were screened solely to identify youth ages 9 to 14; another subset of about 97,000 addresses (or close to 40 percent) were screened to identify youth ages 9 to 17. The remaining addresses (close to 36,000) were screened for adults, youth, and shadow youth ages 9 to 11. These subsamples are referred to as the "YYO" (young youth only ages 9 to 14), "YO" (youth only ages 9 to 17) and "AYS" (adults ages 18 and above, youth ages 12 to 17, and shadow youth ages 9 to 11) replenishment samples, respectively. This replenishment sample was combined for estimation and analysis purposes with Wave 7 adult and youth respondents from the Wave 4 Cohort who were at least age 15 and, in the civilian, noninstitutionalized population at the time of Wave 7. This combined set of Wave 7 participants, 46,169 participants in total, forms the Wave 7 Cohort.
The Adult files contain a single record for every adult participant. The Youth/Parent files contain a single record of every youth who participated in a given wave. Parents who provided permission for their child to complete a Youth Interview were asked to complete a brief Parent Interview that contained questions about parental supervision, school performance, and tobacco use by youth. The Parent Interview is primarily an interview about the child(ren), not the parent. In all four waves, almost all youth had a parent or guardian complete the Parent Interview (over 98.5 percent). When multiple youth from the same household were selected to be in the study, the parent(s) completed separate interviews about each youth. If one parent completed multiple interviews, then questions asked about him or her were only asked once and skipped in the other interview(s). The parent's responses were then duplicated for the other child or children.All data were collected through in-person interviews in Waves 1, 2, 3, 4, and 5. For the continued safety of PATH Study participants and interviewers during the COVID-19 pandemic, data collection for Wave 6 began with telephone interviews only. As conditions improved in certain parts of the country, the PATH Study began in-person interviews with participants on May 7, 2021. All in-person contacts with participants were conducted in compliance with local and state restrictions for COVID-19 mitigation. Wave 6 data were collected with a mix of telephone and in-person interviews. Data collection for Wave 7 began with both telephone and in-person interviews. In addition, a pilot test was conducted to evaluate the feasibility of introducing Web versions of the PATH Study interviews. A sample of continuing adults, parents, and youth was selected to complete the Wave 7 data collection via the Web. Wave 7 data were collected with a mix of telephone, Web, and in-person interviews.
A $2 incentive was mailed to all addresses sampled at Wave 1 and Wave 4 prior to screening. At Wave 7, a $2 incentive was mailed to all addresses in the AYS portion of the replenishment sample. Addresses in the YYO and YO portions of the replenishment sample were prepaid a $5 incentive along with invitation to complete the pre-screener on the Web, and an offer of an additional $5 for completing the online survey. All households that completed the pre-screener received the completion incentive: $5 if the pre-screener was returned via mail or if it was returned via the Web before the nonresponse follow-up mailing; $10 if the pre-screener was returned via the Web after the nonresponse follow-up mailing.Adult respondents were paid $35 for their participation in Wave 1, Wave 2, Wave 3, and Wave 4. In Wave 5, Wave 6, and Wave 7, adult respondents were paid $50 for their participation. In Wave 1, Wave 2, Wave 3, and Wave 4, youth were paid $25 to complete the Youth Interview, and their parents were given $10 for each Parent Interview. In Wave 5, Wave 6, and Wave 7, youth were paid $35 to complete the Youth Interview, and their parents were given $15 for each Parent Interview.
description: In Wave 1, Wave 2, Wave 3, Wave 4, Wave 5, Wave 6, and Wave 7, adults and youth were asked about the following types of tobacco products:


Cigarettes
E-cigarettes/Electronic nicotine products
Cigars (traditional, cigarillos, filtered)
Pipe tobacco
Hookah
Smokeless tobacco (snus pouches and other forms of smokeless tobacco)
Dissolvable tobacco
Bidis and kreteks (youth only)IQOS (starting in Wave 6)Nicotine pouches (starting in Wave 7)Oral tobacco (starting in Wave 7)


Although each section of tobacco products has some unique questions, the majority of the questions fit into one of the following categories:


Ever use
Recency of use
Frequency of use
Amount of use
Brands used
Purchase details
Use of flavored products
Harm and addictiveness
Reasons for use


Additional topics, in at least one wave, include:


Poly use
Nicotine dependence
Packaging and health warnings
Risk and harm perceptions
Secondhand smoke exposure
Marketing and advertising
Media use
Demographics
Health
Psychosocial and mental health
Substance use
Cessation
Social norms
Peer and family influences
COVID-19


Most questions asked in the questionnaires are categorical. Other questions ask, for example, the age at which something occurred or the person's body measurements. Responses to these questions are numerical.
description: Each data file for Wave 1 and 2 contains weights for use in analyses of the data from the complex PATH Study sample design. The weights for Wave 3 have been separated into two files, one for the all-waves weights and one for the single-wave weights. The single-wave weights file is for all respondents in Wave 3 regardless of their participation in Wave 2.
The final full-sample person-level weight for Waves 1 and 2 of the Adult file is R0#_A_PWGT, and the final full-sample person-level weight for Waves 1 and 2 of the Youth/Parent file is R0#_Y_PWGT. The Wave 3 single-wave weight is named R03_A_SWGT for adults and R03_Y_SWGT for youth. The Wave 3 all-waves weights is named R03_A_AWGT for adults and R03_Y_AWGT for youth.
The weights for Wave 4 have been separated into three files corresponding to the Wave 1 and Wave 4 Cohorts and different weight types:
The all-waves weights file is for Wave 1 Cohort respondents who either completed an interview for all waves in which they were old enough or verified their information for waves in which they were not old enough to be interviewed. The Wave 4 all-waves weight for the Wave 1 Cohort is named R04_A_A01WGT for adults and R04_Y_A01WGT for youth.
The single-wave weights file is for all Wave 1 Cohort respondents who completed interviews at Wave 1 and Wave 4. The Wave 4 single-wave weight for the Wave 1 Cohort is named R04_A_S01WGT for adults and R04_Y_S01WGT for youth.
The cross-sectional weights file is for Wave 4 Cohort respondents. The Wave 4 cross-sectional weight for the Wave 4 Cohort is named R04_A_C04WGT for adults and R04_Y_C04WGT for youth.The weights for Wave 5 are in five sets of files corresponding to the Wave 1 and Wave 4 Cohorts and different weight types:
The all-waves weights files are for Wave 1 Cohort participants who completed a Wave 5 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, and 4. The Wave 5 all-waves weight for the Wave 1 Cohort is named R05_A_A01WGT for adults and R05_Y_A01WGT for youth.The Wave 1 Cohort single-wave weights files are for all participants who completed an interview in Wave 1 and in Wave 5, regardless of their participation in the intervening waves. The Wave 5 single-wave weight for the Wave 1 Cohort is named R05_A_S01WGT for adults and R05_Y_S01WGT for youth.The Wave 4 Cohort single-wave weights files are for all Wave 5 interview respondents in the Wave 4 Cohort. The Wave 5 single-wave weight for the Wave 4 Cohort is named R05_A_S04WGT for adults and R05_Y_S04WGT for youth.The Wave 1 Cohort special collection all-waves weights files are for participants who completed a Wave 5 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, and the special collection in Wave 4.5. The Wave 5 special collection all-waves weight for the Wave 1 Cohort is named R05_A_AX01WGT for adults and R05_Y_AX01WGT for youth.The Wave 4 Cohort special collection all-waves weights files are for participants who completed a Wave 5 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Wave 4 and the special collection in Wave 4.5. The Wave 5 special collection all-waves weight for the Wave 4 Cohort is named R05_A_AX04WGT for adults and R05_Y_AX04WGT for youth.The weights for Wave 6 are in six sets of files corresponding to the Wave 1 and Wave 4 Cohorts and different weight types:
The Wave 1 Cohort all-waves weights files are for participants who completed a Wave 6 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, and 5. The Wave 6 all-waves weight for the Wave 1 Cohort is named R06_A_A01WGT for adults and R06_Y_A01WGT for youth.The Wave 4 Cohort all-waves weights files are for participants who completed a Wave 6 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 4 and 5. The Wave 6 all-waves weight for the Wave 4 Cohort is named R06_A_A04WGT for adults and R06_Y_A04WGT for youth.The Wave 1 Cohort single-wave weights files are for all participants who completed an interview in Wave 1 and in Wave 6, regardless of their participation in the intervening waves. The Wave 6 single-wave weight for the Wave 1 Cohort is named R06_A_S01WGT for adults and R06_Y_S01WGT for youth.The Wave 4 Cohort single-wave weights files are for all participants who completed an interview in Wave 4 and Wave 6, regardless of their participation in the intervening waves. The Wave 6 single-wave weight for the Wave 4 Cohort is named R06_A_S04WGT for adults and R06_Y_S04WGT for youth.The Wave 1 Cohort special collection all-waves weights files are for participants who completed a Wave 6 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, 5, and the special collections in Wave 4.5 and Wave 5.5 or PATH-ATS. The Wave 6 special collection all-waves weight for the Wave 1 Cohort is named R06_A_AX01WGT for adults and R06_Y_AX01WGT for youth.The Wave 4 Cohort special collection all-waves weights files are for participants who completed a Wave 6 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 4, 5, and the special collections in Wave 4.5 and Wave 5.5 or PATH-ATS. The Wave 6 special collection all-waves weight for the Wave 4 Cohort is named R06_A_AX04WGT for adults and R06_Y_AX04WGT for youth.
 The weights for Wave 7 are in seven sets of files corresponding to the Wave 1, Wave 4, and Wave 7 Cohorts and different weight types:
The Wave 1 Cohort all-waves weights files are for participants who completed a Wave 7 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, 5, and 6. The Wave 7
all-waves weight for the Wave 1 Cohort is named
R07_A_A01WGT for adults and R07_Y_A01WGT for youth.The Wave 4 Cohort all-waves weights files are for participants who completed a Wave 7 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 4, 5, and 6. The Wave 7 all-waves weight for the Wave 4 Cohort is named R07_A_A04WGT for adults and R07_Y_A04WGT for youth.The Wave 1 Cohort single-wave weights files are for all participants who completed an interview in Wave 1 and in Wave 7, regardless of their participation in the intervening waves. The Wave 7 single-wave weight for the Wave 1 Cohort is named R07_A_S01WGT for adults and R07_Y_S01WGT for youth.* The Wave 4 Cohort single-wave weights files are for all participants who completed an interview in Wave 4 and in Wave 7, regardless of their participation in the intervening waves. The Wave 7 single-wave weight for the Wave 4 Cohort is named R07_A_S04WGT for adults and R07_Y_S04WGT for youth.The Wave 1 Cohort special collection all-waves weights files are for participants who completed a Wave 7 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 1, 2, 3, 4, 5, 6, and the special collections in Wave 4.5 and Wave 5.5 or PATH-ATS. The Wave 7 special collection all-waves weight for the Wave 1 Cohort is named R07_A_AX01WGT for adults and R07_Y_AX01WGT for youth.* The Wave 4 Cohort special collection all-waves weights files are for participants who completed a Wave 7 interview and completed interviews (if old enough to do so) or verified their information (if not old enough to be interviewed) in Waves 4, 5, 6, and the special collections in Wave 4.5 and Wave 5.5 or PATH-ATS. The Wave 7 special collection all-waves weight for the Wave 4 Cohort is named R07_A_AX04WGT for adults and R07_Y_AX04WGT for youth.The cross-sectional weights files are for all Wave 7 interview respondents in the Wave 7 Cohort. The Wave 7 cross-sectional weight for the Wave 7 Cohort is named R07_A_C07WGT for adults and R07_Y_C07WGT for youth.For each weight mentioned above, there are also 100 replicate weights and design variables (VARPSU and VARSTRAT) for use in variance estimation. Detailed information on how these variables were created, and how and why they should be used is provided in the Public-Use Files User Guide.
Note that the weighting procedures adjust for oversampling of specified population groups and nonresponse.<em><strong> ICPSR strongly recommends that researchers read and understand the sections pertaining to weights before analyzing the data to ensure correct use of these variables.</strong></em>
description: Response Rates: The weighted response rates for the PATH Study are shown below. The Wave 1 interview rates are conditional on completion of the Wave 1 screener. The response rates for Waves 2, 3, 4, 5, 6, and 7 are conditional on Wave 1 participation.


Household screener: 54.0 percent
Wave 1 Adult Interview: 74.0 percent
Wave 1 Youth Interview: 78.4 percent
Wave 2 Adult Interview: 83.2 percent
Wave 2 Youth Interview: 87.3 percent
 Wave 3 Adult Interview: 78.4 percent
 Wave 3 Youth Interview: 83.3 percent
 Wave 4 Adult Interview: 73.5 percent
 Wave 4 Youth Interview: 79.5 percent
Wave 5 Adult Interview: 69.4 percent
Wave 5 Youth Interview: 72.3 percent
Wave 6 Adult Interview: 57.5 percent
Wave 6 Youth Interview: 56.6 percentWave 7 Adult Interview: 52.4 percentWave 7 Youth Interview: 54.3 percent


The weighted response rates for the adults and youth in the Wave 4 replenishment sample are shown below. The Wave 4 interview rates for the adults and youth in this sample are conditional on completion of the Wave 4 screener.

 Wave 4 Household screener (for households in which youth and adults were recruited): 52.8

Wave 4 Adult Interview: 68.0 percent
Wave 4 Youth Interview: 70.6 percent
The weighted response rates for the Wave 4 Cohort of the PATH Study are shown below. The response rates for Waves 5, 6, and 7 are conditional on interview response or shadow youth participation at Wave 4 (for replenishment sample members selected as shadow youth).

Wave 5 Adult interview: 88.0 percent
Wave 5 Youth Interview: 83.5 percent
Wave 6 Adult Interview: 73.5 percent
Wave 6 Youth Interview: 63.6 percent
Wave 7 Adult Interview: 66.9 percent
Wave 7 Youth Interview: 55.9 percentThe weighted response rates for the adults and youth in the Wave 7 replenishment sample are shown below. The Wave 7 interview rates for the adults and youth in this sample are conditional on completion of the Wave 7 screener.Wave 7 Household screener: 55.6 percentWave 7 Adult Interview: 55.1 percentWave 7 Youth Interview: 64.0 percent
Please consult the Public-Use Files User Guide for further information regarding response rates.
description: A four-stage stratified area probability sample design was used in the PATH Study, with a two-phase design for sampling adults at the final stage. At the first stage, a stratified sample of geographical primary sampling units (PSUs) was selected, in which a PSU is a county or group of counties. For the second stage, within each selected PSU, smaller geographical segments were formed and then a sample of these segments was drawn. At the third stage, the sampling frame consisted of the residential addresses located in these segments. The fourth stage selected adults and youth from the sampled households identified at these addresses, with varying sampling rates for adults by age, race, and tobacco use status. Adults were sampled in two phases - Phase 1 sampling used information provided in the household screener and Phase 2 sampling used information provided by the adult in the Phase 2 screener at the beginning of the Adult instrument. Please consult the Public-Use Files User Guide for additional details about the sampling.
description: Datasets: 
DS0: Study-Level Files
DS3201: Wave 3: Youth / Parent - All-Waves Weights
DS3202: Wave 3: Youth / Parent - Single-Wave Weights
DS5001: Wave 5: Adult Questionnaire Data
DS5002: Wave 5: Youth / Parent Questionnaire Data
DS4111: Wave 4: Adult - Wave 1 Cohort All-Waves Weights
DS4112: Wave 4: Youth / Parent - Wave 1 Cohort All-Waves Weights
DS4503: Wave 4: All Participants - Ever/Never Reference Data
DS3101: Wave 3: Adult - All-Waves Weights
DS3102: Wave 3: Adult - Single-Wave Weights
DS7711: Wave 7: Adult - Wave 1 Cohort Special Collection All-Waves Weights
DS7712: Wave 7: Youth / Parent - Wave 1 Cohort Special Collection All-Waves Weights
DS4001: Wave 4: Adult Questionnaire Data
DS4002: Wave 4: Youth / Parent Questionnaire Data
DS7331: Wave 7: Adult - Wave 7 Cohort Cross-Sectional Weights
DS7332: Wave 7: Youth / Parent - Wave 7 Cohort Cross-Sectional Weights
DS7721: Wave 7: Adult - Wave 4 Cohort Special Collection All-Waves Weights
DS7722: Wave 7: Youth / Parent - Wave 4 Cohort Special Collection All-Waves Weights
DS7211: Wave 7: Adult - Wave 1 Cohort Single-Wave Weights
DS7212: Wave 7: Youth / Parent - Wave 1 Cohort Single-Wave Weights
DS3503: Wave 3: All Participants - Ever/Never Reference Data
DS7221: Wave 7: Adult - Wave 4 Cohort Single-Wave Weights
DS7222: Wave 7: Youth / Parent - Wave 4 Cohort Single-Wave Weights
DS6711: Wave 6: Adult - Wave 1 Cohort Special Collection All-Waves Weights
DS6712: Wave 6: Youth / Parent - Wave 1 Cohort Special Collection All-Waves Weights
DS3001: Wave 3: Adult Questionnaire Data
DS3002: Wave 3: Youth / Parent Questionnaire Data
DS6721: Wave 6: Adult - Wave 4 Cohort Special Collection All-Waves Weights
DS6722: Wave 6: Youth / Parent - Wave 4 Cohort Special Collection All-Waves Weights
DS6211: Wave 6: Adult - Wave 1 Cohort Single-Wave Weights
DS6212: Wave 6: Youth / Parent - Wave 1 Cohort Single-Wave Weights
DS7111: Wave 7: Adult - Wave 1 Cohort All-Waves Weights
DS7112: Wave 7: Youth / Parent - Wave 1 Cohort All-Waves Weights
DS6221: Wave 6: Adult - Wave 4 Cohort Single-Wave Weights
DS6222: Wave 6: Youth / Parent - Wave 4 Cohort Single-Wave Weights
DS5711: Wave 5: Adult - Wave 1 Cohort Special Collection All-Waves Weights
DS5712: Wave 5: Youth / Parent - Wave 1 Cohort Special Collection All-Waves Weights
DS2001: Wave 2: Adult Questionnaire Data with Weights
DS7121: Wave 7: Adult - Wave 4 Cohort All-Waves Weights
DS2002: Wave 2: Youth / Parent Questionnaire Data with Weights
DS7122: Wave 7: Youth / Parent - Wave 4 Cohort All-Waves Weights
DS5721: Wave 5: Adult - Wave 4 Cohort Special Collection All-Waves Weights
DS7001: Wave 7: Adult Questionnaire Data
DS7002: Wave 7: Youth / Parent Questionnaire Data
DS5722: Wave 5: Youth / Parent - Wave 4 Cohort Special Collection All-Waves Weights
DS5211: Wave 5: Adult - Wave 1 Cohort Single-Wave Weights
DS5212: Wave 5: Youth / Parent - Wave 1 Cohort Single-Wave Weights
DS6111: Wave 6: Adult - Wave 1 Cohort All-Waves Weights
DS6112: Wave 6: Youth / Parent - Wave 1 Cohort All-Waves Weights
DS4321: Wave 4: Adult - Wave 4 Cohort Cross-Sectional Weights
DS4322: Wave 4: Youth / Parent - Wave 4 Cohort Cross-Sectional Weights
DS5221: Wave 5: Adult - Wave 4 Cohort Single-Wave Weights
DS5222: Wave 5: Youth / Parent - Wave 4 Cohort Single-Wave Weights
DS6503: Wave 6: All Participants - Ever/Never Reference Data
DS1001: Wave 1: Adult Questionnaire Data with Weights
DS6121: Wave 6: Adult - Wave 4 Cohort All-Waves Weights
DS6122: Wave 6: Youth / Parent - Wave 4 Cohort All-Waves Weights
DS1002: Wave 1: Youth / Parent Questionnaire Data with Weights
DS6001: Wave 6: Adult Questionnaire Data
DS6002: Wave 6: Youth / Parent Questionnaire Data
DS4211: Wave 4: Adult - Wave 1 Cohort Single-Wave Weights
DS4212: Wave 4: Youth / Parent - Wave 1 Cohort Single-Wave Weights
DS5111: Wave 5: Adult - Wave 1 Cohort All-Waves Weights
DS5112: Wave 5: Youth / Parent - Wave 1 Cohort All-Waves Weights
DS5503: Wave 5: All Participants - Ever/Never Reference Data
description: People who use or do not use tobacco products in the civilian, non-institutionalized household population of the United States aged 9 and older at the time of Wave 1 (Wave 1 Cohort); People who use or do not use tobacco products in the civilian, non-institutionalized household population of the United States aged 10 and older at the time of Wave 4 (Wave 4 Cohort); People who use or do not use tobacco products in the civilian, non-institutionalized household population of the United States aged 9 and older at the time of Wave 7 (Wave 7 Cohort). Smallest Geographic Unit: Census Region
description: audio computer-assisted self interview (ACASI); computer-assisted personal interview (CAPI); computer-assisted telephone interview (CATI); web-based surveyThe data files contain a person-level (PERSONID) variable allowing linkage of people across waves of data collection. The values in this variable are random and contain no direct or indirect personally identifiable information. Please review Chapter 8 in the Public-Use Files User Guide for information on linking files together. The files are sorted by the variable PERSONID.ICPSR attempted to duplicate all information contained in the questionnaires into the question text used in the codebooks. Some of the longer programming instructions were not incorporated into the question text. In these cases, the question text includes a note for the user
to read the full programming instructions in the corresponding section of the questionnaire. Derived and imputed variables contain the algorithms used in the creation of these variables. Users are advised to refer to the Public-Use Files User Guide and annotated questionnaires when reviewing the codebooks.Some variables were withheld to limit releasing information that is a potential risk for disclosure. These variables are listed in Appendix E in the Public-Use Files User Guide.The Youth Interview and Parent Interview questionnaires were distinct and separate questionnaires used in data collection. However, for each wave, both questionnaires have been combined into a single document since the responses to these questionnaires are also combined into a single file.Both the Adult and Youth questionnaires in each wave include several questions about tobacco brands and products the respondent usually uses and most recently used. For each question, a list of response options was displayed on the computer screen for the respondent to select. For many major brands and products, the displayed list included both a text label and a thumbnail image of the brand logo or product package. The displayed list was different for each of the tobacco product types with the brands and products listed being those that were known to exist for the specific tobacco product type. Because these lists are long, they are not provided in a frequency table for each variable in the codebook or in the annotated instrument. For convenience, both the Adult and Youth/Parent codebooks contain an appendix with a frequency table of the top 20 responses for each variable. The PATH Study Master Tobacco Brand and Product Code Guide is available as an Excel workbook file [Documentation.xlsx (Tobacco_Brand)]. The spreadsheets in this Excel workbook file are protected and may not be edited. However, the last spreadsheet contains filters to narrow the complete list. This spreadsheet is the master file of all brand and product responses for these questions from all waves, including any responses that were not in the list of options displayed to the respondent.The PATH Study Adult Variable Crosswalk and the PATH Study Youth Variable Crosswalk are also available as Excel workbook files. The spreadsheets in these Excel workbook files are protected and may not be edited. These crosswalk files are auxiliary files that can be used in conjunction with the annotated instruments and codebooks to quickly compare content across waves. The crosswalk files link questions across waves for each respective instrument so that users can easily identify the number of waves or time points at which data for specific questions are available for analyses.In the Youth/Parent files for Wave 1 and Wave 2 (DS1002 and DS2002), the last section of the questionnaire contains demographic and health history questions. A few of the questions were asked of all youth. However, most questions were only asked of emancipated youth. Conversely, in the Parent Interview section the same questions were asked of parents of all sampled youth with the exception of the emancipated youth. There are a small number of emancipated youth in Wave 3 and later waves, but there are no individual questions asked exclusively of emancipated youth.In both the Adult and Youth/Parent data files, several groups of variables contain the word "RANDOM" in both the variable name and label. This indicates computerized randomization of the question order. These "RANDOM" variables detail the order in which the questions were asked of a respondent.The Wave 1 data files for both Adults and Youth, contain a section about tobacco advertising. There are 20 variable triplets contained in this section. The computer randomly selected 20 advertisements and then asked the respondents whether they had seen the ad and whether they liked the ad. The Image ID variable (_AD) identifies the advertisement that was displayed to the respondent to characterize the ad, e.g., the tobacco product and brand. However, vendors did not grant permission to publicly release the actual .jpg and .bmp files containing the images seen by respondents.Derived and imputed demographic variables (age, sex, Hispanic ethnicity, and race) are included near the end of each data file. An accompanying imputation flag variable is also included. These variables are distinguished by the variable name starting with "R0#R" and contain the word "DERIVED" or "IMPUTED" in the variable label. Imputed variables are only available on the Wave 1 data files.Within the "Derived and Imputed Variables" section of the Wave 1 Adult and Youth/Parent codebooks is one geographic variable - Census Region. The restricted-use files contain additional geographic variables.All Adult and Youth/Parent data files contain additional derived variables. These variables can be distinguished by the variable name starting with "R0#R" and contain the word "DERIVED" in the variable label. There are several variables for each tobacco category to identify certain classes of respondents with current and former tobacco use.In accordance with the study's informed consent, information is suppressed about individuals that withdrew from the PATH Study. Their information was recoded to a special missing value, designated as -97777.The current release contains the public-use versions of Wave 1, Wave 2, Wave 3, Wave 4, Wave 5, Wave 6, and Wave 7 data files.The documentation file named [Documentation.pdf (Informed_Consent)] includes the six consent forms provided to and signed by the respondents for the various types of interviews conducted and biological samples collected. Participants provide consent at their initial interview and biological sample collection; consents remain in effect for all subsequent waves. Aged-up adults who previously responded to the Youth Interview at one wave need to re-consent as an adult at the time of the subsequent wave.The Nonresponse Bias Analysis Report for Wave 1 details the response rates and the potential for bias from nonresponse. There are also Nonresponse Bias Analysis Reports for Wave 2, Wave 3, Wave 4, Wave 5, Wave 6and Wave 7.The Informed Consent Document and Nonresponse Bias Analysis Reports are specific to each wave they are listed for. They are listed for both the Adult File and the Youth/Parent File, but they are the same files.The questionnaires in this collection are updated versions of the fielded questionnaires that were annotated for analytic purposes. Spanish versions of the instruments are available on the restricted-use files home page.The PATH Study's documentation is available for your use and may be reproduced in whole or in part without permission from NIH's National Institute on Drug Abuse or FDA's Center for Tobacco Products. Citation of the source is appreciated.Additional background information including answers to frequently asked questions for study participants and researchers can be found in the Researchers section of the PATH Study series page.The Public-Use Files User Guide provides an overview of the entire PATH Study. The guide covers topics such as sample design, data collection, weighting, response rates, analytic considerations, and programming syntax to run common statistics and link the files together. Researchers should feel free to use the information in the User Guide for their publication and the guide should be cited as follows:


United States Department of Health and Human Services. National Institutes of Health. National Institute on Drug Abuse, and United States Department of Health and Human Services. Food and Drug Administration. Center for Tobacco Products. Population Assessment of Tobacco and Health (PATH) Study [United States] Public-Use Files, User Guide. ICPSR36498-v8 Ann Arbor, MI: Inter-university Consortium for Political and Social Research [distributor], 2018-09-28. http://doi.org/10.3886/ICPSR36498.userguideThe data for the PATH Study was collected and prepared by Westat. The contract numbers under which they performed their work are: HHSN271201100027C and HHSN271201600001C.