The Effects of Trigger Events on Changes in Children's Health Insurance Coverage. 2. Frequency of Prior Events

04/18/2000

For each of the four sets of transitions--consisting of exits from (1) ESI, (2) uninsurance, (3) Medicaid, and (4) other insurance--we examined the frequency of alternative events occurring in conjunction with transitions into each of the three alternative destination statuses. We also examined the frequency of events occurring over the same time period among children who made no transition --that is, children who remained (1) covered by ESI, (2) uninsured, (3) covered by Medicaid, or (4) covered by other insurance. Comparing the frequency of individual events among children who made one of three transitions and children who made no transition provides a way of gauging the strength of the association between individual events and the transitions they preceded. An event that occurred with equal frequency among children who made a transition and those who did not is unlikely to have had a role in triggering the transition--no matter how often the event occurred among children who made the transition. On the other hand, an event that occurred ten times as often among children who made a transition as it did among children who did not make the transition has at least a strong association with the transition and may have had a role as a trigger as well.

For each of the four categories of coverage, the first column of Table 7 displays the average monthly number of children who were in that category prior to the transition month, the number who made each of three possible transitions, and the number who remained in that category through the transition month (that is, did not change coverage). 16 In the tables that follow, we show how often each of these outcomes was preceded or accompanied by a potential trigger event. The second column reports the one-month transition rates from each of the four initial categories of coverage to each of the four possible outcomes: transitions to any of three alternative categories versus no change in coverage. These transition rates were calculated by dividing the average number of transitions to each outcome by the average number of children who shared the same initial coverage in the prior month, and then multiplying the result by 100 percent. Children with ESI had the lowest exit rate, with only 1.4 percent moving to another coverage in the next month. By contrast, uninsured children and children with other insurance had exit rates in excess of 7 percent while children with Medicaid had an intermediate exit rate of 3.7 percent.

TABLE 7: AVERAGE MONTHLY NUMBER OF TRANSITIONS AND TRANSITION RATES, BY TYPE
Coverage in Prior Month and Type of Transition Average
Monthly
Number
Percent of
Prior Month
Total
 
   Children with ESI in Prior Month 41,846,400 100.00
 
Transitions from ESI to:    
   Uninsured 301,600 0.72
   Medicaid 143,300 0.34
   Other Insurance 153,300 0.37
Children Retaining ESI* 41,248,200 98.57
 
   Children Uninsured in Prior Month 9,000,700 100.00
 
Transitions from Uninsured to:    
   ESI 295,500 3.28
   Medicaid 303,300 3.37
   Other Insurance 53,700 0.60
Children Remaining Uninsured* 8,348,200 92.75
 
   Children with Medicaid in Prior Month 13,191,600 100.00
 
Transitions from Medicaid to:    
   Uninsured 322,700 2.45
   ESI 149,800 1.14
   Other Insurance 17,400 0.13
Children Retaining Medicaid* 12,701,700 96.29
 
   Children with Other Insurance in Prior Month 2,791,800 100.00
 
Transitions from Other Insurance to:    
   ESI 148,100 5.30
   Uninsured 45,600 1.63
   Medicaid 9,400 0.34
Children Retaining Other Insurance* 2,588,700 92.73
 
* Children with no transition in next month.

SOURCE: Survey of Income and Program Participation, 1992 Panel.

We looked at events over two time periods: one month and six months preceding the transition. Our findings are summarized in Table 8, which reports the percentage of children who experienced one or more events out of a set of possible events among children who experienced a particular transition. In each case the frequency of events among children who experienced a transition is contrasted with the percentage who encountered any of the same events among children who did not change coverage. For example, in the first row we find that 46.7 percent of the children who moved from ESI to uninsured experienced a possible trigger event in the prior month compared to only 8.8 percent of those who remained covered by ESI. If we look back six months instead of just one, the fraction of children who experienced a possible trigger event rises to 71.0 percent among children who moved from ESI to uninsured and 34.7 percent among children who remained covered by ESI. Generally, the set of events that we defined as relevant varied with the type of transition--even among children who shared the same coverage in the prior month. 17 Therefore, even though the comparison group of children without transitions is the same for all children who exited the same coverage, the frequency of prior events among children with no transition need not be the same in each case, and indeed it is not.

TABLE 8: FREQUENCY OF TRIGGER EVENTS AMONG CHILDREN WITH AND WITHOUT A TRANSITION, BY TYPE OF TRANSITION
Type of Transition Children
With a
Transition
Children
With No
Transition
Children
With a
Transition
Children
With No
Transition
  Percent of Children with a
Trigger Event in Prior Month
Percent of Children with a Trigger
Event in Previous Six Months
 
Transitions from ESI to:
   Uninsured 46.7 8.8 71.0 34.7
   Medicaid 29.3 6.6 53.2 25.2
   Other Insurance 46.6 12.5 66.8 45.3
 
Transitions from Uninsured to:
   ESI 38.6 13.9 70.8 49.9
   Medicaid 41.2 12.8 67.5 49.2
   Other Insurance 49.7 17.3 74.6 59.7
 
Transitions from Medicaid to:
   Uninsured 41.6 11.4 74.9 40.1
   ESI 34.1 11.4 64.6 40.1
 
Transitions from Other Insurance to:
   ESI 44.3 12.0 67.2 43.8
   Uninsured 48.1 18.8 74.0 58.8
 
SOURCE: Survey of Income and Program Participation, 1992 Panel.

NOTE: Children with no transition are children who remained covered by ESI (panel 1), remained uninsured (Panel 2), remained covered by Medicaid (panel 3), or remained covered by other insurance (panel 4). Because of the small sample sizes of children leaving Medicaid and obtaining other insurance, and vice versa, we did not calculate the frequency of trigger events for these transitions. See Tables 10 through 13 for identification of the trigger events that are included for each type of transition.

TABLE 9: NUMBER OF TRANSITIONS AND FREQUENCY OF TRIGGER EVENTS BY
WHETHER TRANSITION WAS REVERSED AND TYPE OF TRANSITION
Type of Transition Transitions
That Were
Reversed in
Four Months
Transitions
That Were
Not
Reversed
Transitions
That Were
Reversed in
Four Months
Transitions
That Were
Not
Reversed
  Average Monthly Number Percentage of Children with a
Trigger Event in Prior Month
 
Transitions from ESI to:
   Uninsured 95,800 204,800 40.5 49.3
   Medicaid 67,500 75,800 22.1 35.8
   Other Insurance 52,100 101,200 44.1 47.8
 
Transitions from Uninsured to:
   ESI 55,000 240,100 27.0 41.3
   Medicaid 101,100 200,500 29.2 47.6
   Other Insurance 15,100 38,600 44.4 51.8
 
Transitions from Medicaid to:
   Uninsured 111,400 206,900 38.6 42.2
   ESI 23,500 123,700 51.1 30.6
 
Transitions from Other Insurance to:
   ESI 16,300 29,300 59.8 35.8
   Uninsured 33,400 114,700 39.0 50.8
 
SOURCE: Survey of Income and Program Participation, 1992 Panel.

The comparative frequencies of events in the prior month show a clear association between the occurrence of possible trigger events and the occurrence of a change in coverage. In the prior month, possible trigger events occurred three to five times more often among children who experienced a transition than among children who did not. Depending on the type of transition, between 29 to 48 percent of transitions had at least one possible trigger event in the prior month, with most of the rates being above 40 percent. Possible trigger events occurred least often among children who moved between ESI and Medicaid (in either direction) and most often among children who moved between uninsured and other insurance (also in either direction).

Lengthening the reference period by five months increased the number of events, of course, but equally if not somewhat more so among children with no transitions than among children with transitions. 18 The net result is that the differentials between children with and without transitions are generally weaker when events as far back as six months as opposed to just one month are included. Why do the differentials become less pronounced over time? One possibility, of course, is that trigger events generate transitions relatively quickly rather than over a period of several months. A parent's losing employment may have an immediate impact on the ESI coverage of parent and child. Another factor contributing to this phenomenon is the seam bias in the reporting of transitions in the SIPP. With most transitions in coverage and many trigger events being "moved" to the nearest seam between interview reference periods, events that occurred as far apart as three or four months may be reported in the same month. In the tables discussed below, we report events occurring in the prior month. Six-month tables are included in the Appendix.

The incidence of prior events also provides additional information with which to assess the plausibility of different types of transitions. Earlier we presented evidence that changes in respondent--a potential source of reporting error--were no more common when transitions were reported to have been reversed within four months than when they were not reversed. Changes in respondent are only one source of response error. Here we ask whether transitions that were reversed within four months were less likely to have been preceded by possible trigger events than transitions that were not reversed. Table 9 summarizes our findings. Comparing the final two columns, we see that for eight of the ten transition types, potential trigger events were less common among transitions that were reversed than among transitions that were not reversed, but in every case these events were still much more common than they were among children with no transitions. Moreover, the transitions that seemed most likely to reflect respondent confusion--those between ESI and other insurance (in both directions)--are the most strongly supported by Table 9. We interpret these findings as suggesting that, at worst, transitions that were reversed were somewhat more likely to have been misreported than transitions that were not reversed. 19 Alternatively, it may be that trigger events of the kind we have examined here simply play a less important role in explaining transitions that are quickly reversed than they do in accounting for other transitions. 20

View full report

Preview
Download

"triggers.pdf" (pdf, 241.38Kb)

Note: Documents in PDF format require the Adobe Acrobat Reader®. If you experience problems with PDF documents, please download the latest version of the Reader®