ALLC 1992 - childhood acute lymphoblastic leukaemia - data structure and protocols

Contents List

• ALLC 1992 - childhood acute lymphoblastic leukaemia
• Master list of all centres/groups, trials/strata and treatments (intranet only at present)
• ALLC 1992 data preparation: brief written protocol
• Specification of ALLC 1992 'pink form' format
• ALLC 1992 data form rubric
• Analysis details: endpoints, steering files and strata for ALLC 1992

ALLC 1992 data preparation: brief written protocol

All patient records are converted into 'pink form' (1992) format (described below) if not already supplied in it. Results received as tables are converted into sets of synthetic 'pink form' records. The following routine checks (where appropriate) are performed on every 'pink form' compilation:

• Duplicate patient entries
• Patient identifier missing
• Gender missing
• Birth date missing
• Initial w.b.c. missing
• Diagnosis date missing
• Randomisation date missing
• Treatment allocation missing
• First complete remission date missing
• First event type missing
• First event date missing
• Survival status missing
• Death date missing
• Birth date wrong or out of range
• Diagnosis date wrong or out of range
• either Diagnosis date after, or more than 1y before randomisation date
• or Diagnosis date before, or more than 1y after randomisation date
• Randomisation date wrong, before 1945 or out of range
• First complete remission date wrong or out of range
• First complete remission date more than 1y after diagnosis date
• First event date wrong or out of range
• Last follow-up or death date wrong or out of range
• Gender code unknown
• Randomisation age over 25
• Initial w.b.c. out of range
• Treatment allocation code unknown
• First event type code unknown
• Testicular relapse reported in female patient
• Survival status code unknown
• Cause of death given when alive
• 'Remission death' specified with non-'dead' status
• Two different death dates given

If an event such as relapse is reported at a date later than the quoted last follow-up date, the last follow-up date is automatically changed to the later date. The completeness of follow-up is then calculated for the end of each calendar year. The distributions of randomisation dates, randomisation ages, time elapsed since last follow-up and log w.b.c. are checked for any significant imbalance between treatment groups in two ways as follows. Firstly, a t-test is applied to the difference between the mean value of each distribution for patients in each group with the corresponding mean for patients in the remainder. Secondly, an F-ratio is calculated for each distribution by comparing the variance between the groups with the variance within the groups. The distribution of time elapsed since last follow-up is also checked in these two ways for any significant imbalance between those patients with and those patients without a subsequent recorded event. Finally, the distribution of time elapsed since randomisation is checked in the same two ways for any significant imbalance between patients in the two categories of known gender, the four categories of age and the four categories of known w.b.c.

Where patient serial numbers form an obvious sequence it is checked for missing numbers.

A tabulated breakdown of variables is produced for each trial, together (where relevant) with lists of patients in 'problematical' categories such as those with lapsed follow-up, uncertain death cause or second malignancy site. Graphs of accrual date and the proportion of living patients still on follow-up as a function of time from randomisation by treatment allocation are also produced, together with Kaplan-Meier life-table curves. Before trial data are finally incorporated into the overview, the analyses described above are sent to the participating trialist(s) for checking and approval.

Contact

Vaughan Evans
Childhood A.L.L. Workshop Secretariat
C.T.S.U.
Radcliffe Infirmary
Oxford OX2 6HE
England
Tel. U.K.(44)-Oxford(1865)-557241; FAX: U.K.(44)-Oxford(1865)-558817

Specification of ALLC 1992 'pink form' format

ALLC 1992 data form rubric

[Link to 131 kb JPEG picture of the ALLC 1992 data form here]

GUARANTEE OF CONFIDENTIALITY OF DATA

ANY INFORMATION PROVIDED TO THE CHILDHOOD A.L.L. WORKSHOP SECRETARIAT WILL BE HELD SECURELY AND IN STRICT CONFIDENCE.

NOTES ON FORMAT OF DATA REQUESTED OVERLEAF

Special coding conventions

Please accompany these forms by an explanatory letter about any special coding conventions (e.g. on site of first recurrence, cause of death) you have used, plus notes on any special features of the study(s) to which you wish to draw particular attention.

Dates that are not (or not yet) known exactly

either leave DAY blank, and give (approximate or provisional) month and year;
or leave DAY and MONTH blank, and just give approximate year.

BASELINE DATA

Patient identifier

Any convenient convention you wish, in case any correspondence becomes necessary. (If reporting several trials, please try to use a system that implicitly specifies both the trial and the patient.)

Date of birth

See note above on approximate dates.

Gender

1 = male; 2 = female.

Initial w.b.c:

Initial leucocyte count (units: 10⁹ per litre).

Date of diagnosis

See note above on approximate dates.

Date of 1st randomisation

Date on which the primary treatment was randomised. Please include ALL patients EVER randomised. Ignore all non-randomised patients. See note above on approximate dates.

Trt. gp. allocated

Treatment group number at first randomisation: 1 or 2 only, for 2-group trials, or a wider range for trials with more arms, as defined by you at the top of the form. N.B: even if, in reality, some quite different (or even opposite!) treatment was inadvertently given, what is wanted is the originally-allocated treatment. (For patients erroneously entered more than once, give only the initial allocation.)

FOLLOW-UP DATA

Date of 1st complete remission

Use your own definition of complete remission, but please give this date even if complete remission was achieved on second-line or non-protocol treatments. Please leave blank if complete remission was not achieved. See note above on approximate dates.

Date of 1st recurrence

See note above on approximate dates.

Site of 1st recurrence

Please use your own coding convention and send it to us; or use D = death in remission; H = haematological relapse; C = C.N.S. relapse; T = testicular relapse; O = other relapse; HT = combined haematological and testicular relapse; HTC = combined haematological, testicular and C.N.S. relapse; etc.

Date died/last traced

Date of death, or date last known to be alive, as accurately as possible: see note above on approximate dates.

Dead/other

1 = alive when last traced; 2 = known to be dead.

Death cause (if died in remission)

Please use your own coding convention and send it to us. Alternatively, please send a separate list giving causes of death for patients dying in remission, in whatever format is most convenient for you.

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[End of document, updated to 1 September 2000]