# Presentation: 547725

## The Effect of Unsatisfactory Specimens on Newborn Screening

- Lisa Kalman, PhD
- Newborn Screening Quality Assurance Program, CDC

## How do unsat rates, criteria and practices differ between states?

**       ****?**

## National Unsat Survey 

- Data on state unsat rates was collected from the 1996-2000 National Newborn Screening Reports.  The average unsat rate for each state was calculated from the available data.
- Data on state unsat practices (2001) was collected by email and phone survey.

## Slide 4

## Why Do States Have Different Unsat Rates?

-    ?

## Do states that do not test unsats have a lower unsat rate?

**Idea – Perhaps hospitals will collect better specimens if they know that unsats will not be tested...**

## Data from 49 of 51 programs

**Data from 49 of 51 programs**
**TX tests one class of unsats**

## There is not a significant difference in unsat rates between states that test or do not test (reject) unsat specimens. 

** ****States That....**

-                        _**Reject Unsats       Test Unsats**_
**Mean **** **       1.7% Unsats                      2.3% Unsats
-                          (S.D=1.3)                                 (S.D. = 2.8)
**Median**      1.2% Unsats                1.3% Unsats

- There is not a significant difference in unsat rates between states that test or do not test (reject) unsat specimens.

## Does the number of unsat critera affect the state unsat rate?

- Perhaps states with more unsat criteria have higher unsat rates?

## Unsat Criteria

- 48 of 51 programs reported their unsat criteria
- The number of unsat criteria per state varied from 6 to 20.  The median was 9.
- Most states adopt some or all of the 8 Schleicher and Schuell criteria.
- States also list additional criteria
- We found that the number of unsat criteria is apparently not related to the state unsat rate.

## Summary of Unsat Rate Variation Study

- We were unable to identify reasons for the variation in state unsat rates.

## Do unsats delay newborn screening result reporting  ?

- Examine effect of unsats in two states with different...
- % Unsats
- # of Births/yr
- Screening schemes (1 vs 2 required specimens)
- Follow-up procedures

## The effect of unsatisfactory specimens on newborn screening in two states

- Data from unsat specimens and satisfactory specimens of matched controls were collected from 2001 newborn screening records in two states
- State 1 requires 1 specimen/baby, high # births/yr, high % unsats
- State 2 requires a second screen after day 7, low # births/yr, low % unsats

## Data collected or calculated from unsats and age/weight/date matched controls included...

- Unsat type (for unsat specimens)
- Age at collection
- Birth weight
- Mailing times
- Date of receipt at lab
- Time between specimens
- Age when result from first satisfactory specimen is available

## Number of specimens analyzed.....

- State 1:  n = 1505 unsats/matched controls   (representing 5 weeks of 2001)
- State 2:  n = 359 unsats/matched controls                           (representing most of 2001)
- Some unsats were excluded from analysis due to difficulties with control matching

## State 1 - One required specimen - Median number of days 

**State 1 - One required specimen - Median number of days**** **

## State 1 – Ages when results from a satisfactory specimen are available

## State 1 - 

- 66% of patients with unsats eventually got a satisfactory repeat specimen
- 34% of patients with unsats were not documented to have a satisfactory repeat specimen
- Of the 34% with no satisfactory repeat:
-  59% had no repeat specimen
-  41% had only unsat repeats

## State 2 - Two Required Specimens - Median number of days

**Birth**

**Collection of first specimen ****Satisfactory**

**Collection of second specimen ****Satisfactory**

**Specimen arrives at lab**

**Specimen arrives at lab**

**Test results released**

**Satisfactory Specimens**

**Test results released**

**3 days**

**3 days**

**9 days**

**7 days**

**20 days**

**Birth**

**Collection of first specimen****Unsat**

**Collection of second specimen ****Satisfactory**

**Specimen arrives at lab**

**Specimen arrives at lab**

**Test results released**

**Unsatisfactory 1****st**** Specimen = 62% of total unsats**

**Unsat reported**

**3 days**

**4 days**

**8 days**

**24 days**

## State 2 - Two Required Specimens - Median number of days

## State 2 – Ages when results from a satisfactory specimen are available

**1****st**** Specimen**

**2****nd**** Specimen**

## State 2 - 

- 91% of babies with and unsat 1st specimen (62% of all unsats) had a satisfactory repeat specimen
- 9% of patients with unsat 1st specimens were not documented to have a satisfactory repeat specimen
- Of these 9% without satisfactory repeat:
- 67% had no repeat specimen
- 33% had unsat repeats

## State 2 (cont)......

- 5.6% of all patients with unsats (1st or 2nd) were not documented to have _any_ satisfactory specimen
- (9% of 62% = 5.6%)

## Conclusions – State 1

- Babies with unsat 1st specimens got valid results 16 days later (median difference) than children with a satisfactory 1st specimen (29 vs 13 days)
- 34% of patients with unsats were never documented to have a satisfactory repeat specimen – this state does not follow up unsat specimens

## Conclusions – State 2

- Babies with unsat 1st specimens got valid results 18 days later (median difference) than children with a satisfactory 1st specimen (24 vs 7 days)
- The impact of an unsat 2nd specimen is lessened since these patients had results from a satisfactory 1st specimen
- 5.6% of all patients with unsat specimens were never documented to have a satisfactory specimen - this state has aggressive follow up procedures and a mandatory second specimen

## Bottom Line

- The delay and possible false negative results caused by unsats could potentially cause harm to affected children
- Need to scientifically analyze unsat specimens to determine which categories are really unsuitable for testing
- Need to improve specimen collection (education)
- Need electronic specimen linking and tracking
- Need aggressive follow up of unsats

## Others involved in these studies....

- Scott Grosse, CDC
- Owen Devine, CDC
- Harry Hannon, CDC
- Brad Therrell, NNSGRC
-  Special Thanks to:
- The Newborn Screening Staff in States 1 and 2