Carnegie Mellon University

Major Stressful Life Events (Interview)


Life Events and Difficulties Schedule (LEDS)


PCS1, PCS2* (partial data; see below)

Primary References

1. Brown, G. W., & Harris, T. O. (Eds.). (1989). Life events and illness. New York: Guilford Press.

2. Harris, T. O. (1991). Life stress and illness: The question of specificity. Annals of Behavioral Medicine, 13, 211-219.

3. Wethington, E., Brown, G. W., & Kessler, R. C. (1995). Interview measurement of stressful life events. Measuring stress: A guide for health and social scientists, 59-79.


To determine whether participants experienced a severe acute event and/or a severe chronic difficulty during the last year. Acute events have durations of less than 1 month, with most lasting only hours or minutes (e.g., a severe reprimand at work or a fight with a spouse). Difficulties typically last a month or more and involve the disruption of everyday routines (e.g., ongoing marital problems or unemployment).


Life stressors were assessed by a standardized semistructured interview, the Bedford College Life Events and Difficulties Schedule (LEDS; Brown & Harris, 1989; Harris, 1991). The LEDS provides a number of significant advantages over the checklist approach to the assessment of life events, including strict criteria for what constitutes a stressful life event; classification of each event on the basis of severity of threat, emotional significance, and domain of life experience in which it occurred (e.g., work, relationship); identification of the temporal course (onset and offset) of each event; and information on the extent to which persons of various levels of intimacy with the respondent are involved in the event. The LEDS has been found to have acceptable levels of reliability and validity (Brown & Harris, 1989; Wethington, Brown, & Kessler, 1995).  Using a reference period of the past 12 months, respondents are asked about the occurrence of 95 possible life events that can be categorized into 10 different life domains:  education, work, reproduction, housing, money/possessions, crime/legal, health/treatment/accidents, marital/partner relationship, other relationships, and miscellaneous.  Items comprising the LEDS event list consist of questions about consensually-defined negative events (e.g., job loss, divorce, bereavement), role transitions (e.g., births, promotions, graduation from school), and situations that may have involved a severe emotional reaction but are not typically defined as events in checklists (e.g., breaking bad news to a non-close other). 

Identified events are then probed by the interviewer to obtain details regarding the surrounding context of the event.  From this information, the interviewer creates a narrative description of the event which is then coded according to its duration, focus, and potential for long-term contextual threat.  Stressors with durations of less than one month are coded as events, whereas stressors lasting for longer than one month are coded as difficulties.  Focus concerns whether the event directly involves the respondent; involves another person or persons but excludes the respondent; or involves both the respondent and another person or persons.  Potential for long-term contextual threat is rated by the interviewer based on ratings given to other similar events in the LEDS dictionary and is informed by the details obtained from the probing interview (see Wethington, et al., 1995).  Ratings range from 1 (marked threat) to 4 (little or no threat). 

Major Stressful Life Events

Using data collected from the LEDS, we derived several measures of major stressful life events.  We selected events based on the LEDS classification of provoking agents.  Provoking agents are defined as events that have a severity rating of 1 or 2 and directly involve the respondent or the respondent and another person or persons.

Both PCS1 and PCS2 contain variables identifying provoking agent events within each of the aforementioned 10 domains, as well as the total number of provoking agent events across all domains.  PCS1 also contains variables indicating the total number of negative life stressors (leds.negev_tot; includes both events with ratings of 1, 2, or 3 and all difficulties irrespective of threat rating) as well as information on the duration of individual life events (see PCS1 data codebook for these and other LEDS event variables.)  The table below lists the events variables included in the data set along with the LEDS construct they represent (if applicable) and a brief definition.  All variables are available in 2 forms: as a dichotomous variable indicating whether an event meeting the definition occured and as a continuous variable indicating the total number of occurrences of that type of event.

Variable Name

LEDS Construct



Severe event

Long-term contextual threat rating of 1 or 2


Event with long-term contextual threat

Long-term contextual threat of 1 or 2; AND threat is still present 10-14 days following onset.


Event with short-term contextual threat

Short-term contextual threat of 1 or 2; AND peak threat of the event within first one or two days.


Provoking agent

Long-term contextual threat rating of 1 or 2; AND subject or joint-focused



Education provoking agent events



Work provoking agent events



Reproduction provoking agent events



Housing provoking agent events



Money/possessions provoking agent events



Crime/legal provoking agent events



Health/treatment/accidents provoking agent events



Marital/partner relationship provoking agent events



Other relationship (including child) provoking agent events



Miscellaneous provoking agent events (including pets) and death



Marital/relationship loss provoking agent events (PCS1 only)


Unresolved event

Event wherein “date of occurrence” variable is not blank and there is no “date of neutralization”



Event linked to a difficulty (PCS1 only)



Includes both events with ratings of 1, 2, or 3 and all difficulties irrespective of threat rating (PCS1 only)

Chronic Difficulties

Due to a restructuring of the laboratory that conducted the LEDS scoring, data on chronic difficulties are only available for PCS1.  To be identified as a difficulty, a chronic stressor must have lasted 1 month or longer; could not have ended more than 6 months prior to viral challenge; and had a contextual severity rating of 1, 2, or 3 (Q6 criterion cited in codebook).  In addition, if the chronic stressor was health-related, it needed to have resulted in at least one of the following outcomes (Q4 criterion cited in codebook):  major role change (e.g., giving up job); major caring responsibility (e.g., constant care or supervision of another); major stigma or embarrassment (e.g., HIV+ status, severe mental handicap).  Among the several difficulties variables included in the PCS1 data set are total number of difficulties lasting 1 month or longer, 6 months or longer, and 24 months or longer.  Difficulties also are categorized based on whether they are interpersonal in nature (see PCS1 data codebook). 


Prior to being administered the LEDS, participants completed a brief demographic interview (PCS1, PCS2). The interview was designed to collect information that would facilitate raters’ judgments of the contextual threat associated with participants’ experienced life events and difficulties.  This information includes conventional sociodemographic information such as age, sex, race, and marital status, as well as data on childhood experiences such as birth order, religious upbringing, and whether the respondent attended a traditional grade school or boarding school.  The LEDS demographics interview also collects some information on social relationships such as number of children and grandchildren, number of friends, and number of confidants.

*PCS2 LEDS data are complete for life events only.  Due to restructuring of the laboratory that conducted the LEDS scoring, data on difficulties are not available.

Number of Items

LEDS: Varies

LEDS demographic interview: 25


Not available