BC 1995 - breast cancer - data structure and protocols

Contents List

BC 1995 - breast cancer

BC 1995 data preparation: brief written protocol
Specification of BC 1995 'pink form' format
BC 1995 data form rubric
Guide to coding some death causes in BC 1995 data format

Analysis details: endpoints, steering files and strata for BC 1995

BC 1995 data preparation: brief written protocol

Strict confidentiality of trial results is observed. Information is held in the Clinical Trial Service Unit computers in a form which can be accessed only by known individuals.

All patient records are converted into 'pink form' (1995) format (described below) if not already supplied in it. Results received as tables are converted into sets of synthetic records. The following routine checks (where appropriate) are performed on every compilation:

Duplicate patient entries
Patient identifier missing
Randomisation date missing
Treatment allocation missing
Randomisation age missing
Menopausal status missing
Surgery type missing
Axillary status missing
Oestrogen receptor measurement missing
Progesterone receptor measurement missing
Second malignancy site missing
Second malignancy date missing
Distant/unknown recurrence flag missing
Distant/unknown recurrence date missing
Prior local recurrence flag missing
Prior local recurrence date missing
Survival status missing
Death date missing
ICD revision missing
Cause of death missing
Randomisation date wrong, before 1945 or out of range
Second malignancy date wrong or out of range
Distant/unknown recurrence date wrong or out of range
Prior local recurrence date wrong or out of range
Last follow-up or death date wrong or out of range
Treatment allocation code unknown
Randomisation age not in range 20-89
Menopausal status code unknown
Surgery code unknown
Axillary status code unknown
Oestrogen receptor status code unknown
Progesterone receptor status code unknown
Second malignancy site code unknown
Distant/unknown recurrence flag error
Prior local recurrence flag error
Survival status code unknown
ICD revision unknown
Death cause code unknown
Cause of death given when alive

The total numbers of patients and the distributions of randomisation age, menopausal status, axillary nodal status, oestrogen receptor status and progesterone receptor status are checked for any significant imbalance between treatment groups. These five distributions are compared as follows. Patients are grouped into three categories according to randomisation age (below 50 years; 50 - 69 years or unknown; 70 years or above) and a chi-squared test is applied to the population of the three categories found in each treatment group. Similarly, three categories are formed for menopausal status (pre- or perimenopausal; unknown; postmenopausal), for axillary nodal status (negative; unknown; positive), for oestrogen receptor status (poor; unknown; positive) and for progesterone receptor status (poor; unknown; positive) and these are tested in the same way as the categories formed for randomisation ages.

If an event such as the recurrence of disease 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 and time elapsed since last follow-up 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 recorded recurrence of disease. Finally, the distribution of time elapsed since last follow-up is checked in the same two ways for any significant imbalance between patients in two categories of menopausal status (pre- or perimenopausal; postmenopausal), two categories of axillary nodal status (negative; positive), two categories of oestrogen receptor status (poor; positive) and two categories of progesterone receptor status (poor; positive).

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 patents 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

Please address inquiries concerning data preparation and checking to:

Vaughan Evans

EBCTCG 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 BC 1995 'pink form' format

Item

Description

FORTRAN

Columns

Details

Abbreviation

Trial/stratum identifying code

1 - 6

Trial

Patient identifier (or sequence number)

A12

8 - 19

Patient

Randomisation date

21 - 26

DDMMYY

Rand. Date

Treatment group allocated (as on master list)

Trt. Grp

Randomisation age

30 - 31

years

Age

Menopausal status on entry

Value	Description	Abbreviation
1	Pre-menopausal	Pre
2	Peri-menopausal	Peri
3	Post-menopausal	Post
4	Artificial	Arti

Meno

Surgery: first mastectomy

35 - 36

Value	Description	Abbreviation
1	Radical	Rdcl
2	Total	Totl
3	Simple without clearance	SimN
4	Partial with clearance	ParY
5	Partial without clearance	ParN
6	Lumpectomy with clearance	LumY
7	Lumpectomy without clearance	LumN
8	Partial, clearance unknown	Par?
9	Lumpectomy, clearance unknown	Lum?
10	Subcutaneous	Subc
11	Simple with clearance	SimY
12	Other	Othr
13	None	None

Surg

Axillary status on entry

37 - 38

Value	Description	Abbreviation
1	N0 (clearance)	pN0
2	N1-3 (clearance)	pN1-3
3	N4+ (clearance)	pN4+
4	N- (sample only)	sN-
5	N+ (sample only)	sN+
6	N- (clinical)	cN-
7	N+ (clinical)	cN+
8	N- (method unknown)	?N-
9	N+ (method unknown)	?N+
10	N+ (clearance)	pN+
11	Benign lesion	Benign
12	N- (clinical) N0 (clearance)	cN-pN0
13	N- (clinical) N+ (clearance)	cN-pN+
14	N+ (clinical) N0 (clearance)	cN+pN0
15	N+ (clinical) N+ (clearance)	cN+pN+
16	Not breast cancer	Not BC

Axilla

Oestrogen receptor measurement (fmol/mg protein)

40 - 43

Value	Description	Abbreviation
fmol/mg protein
-1	Negative	ERpoor
-2	Marginal	ERpoor
-3	Positive	ER+
-4	< 10 fmol/mg protein	ERpoor
-5	10 - 19 fmol/mg protein	ER+
-6	20 - 29 fmol/mg protein	ER+
-7	30 - 49 fmol/mg protein	ER+
-8	50 - 99 fmol/mg protein	ER+
-9	100+ fmol/mg protein	ER++
-10	10 - 29 fmol/mg protein	ER+
-11	30 - 100 fmol/mg protein	ER+
-12	10 - 99 fmol/mg protein	ER+
-13	0 fmol/mg protein	ER0
-14	10 - 49 fmol/mg protein	ER+

Est. Rec., E.R.

Progesterone receptor measurement

45 - 48

Value	Description	Abbreviation
fmol/mg protein
-1	Negative	PRpoor
-2	Marginal	PRpoor
-3	Positive	PR+
-4	< 10 fmol/mg protein	PRpoor
-5	10 - 19 fmol/mg protein	PR+
-6	20 - 29 fmol/mg protein	PR+
-7	30 - 49 fmol/mg protein	PR+
-8	50 - 99 fmol/mg protein	PR+
-9	100+ fmol/mg protein	PR++
-10	10 - 29 fmol/mg protein	PR+
-11	30 - 100 fmol/mg protein	PR+
-12	10 - 99 fmol/mg protein	PR+
-13	0 fmol/mg protein	PR0
-14	10 - 49 fmol/mg protein	PR+

Prg.Rec., P.R.

Site of second malignancy

50 - 53

Value	Description	Abbreviation
ICD9
140x	Lip	Lip
141x	Tongue	Tongue
142x	Salivary glands	Salivary
143x	Gingival	Gingival
144x	Mouth floor	MouFloor, OraF
145x	Oral (general)	Oral
146x	Oropharyngeal	Opharynx
147x	Nasopharyngeal	Npharynx
148x	Hypopharyngeal	Hpharynx, Hpha
149x	Oral / throat (general)	OralThro, Oral
150x	Oesophageal	Oesophag, Oeso
151x	Gastric	Gastric, Gast
152x	Small intestine / duodenal	SmallInt, SBow
153x	Colon / colorectal (general)	Colon, CoRe
154x	Rectal	Rectal, Rect
155x	Hepatic	Hepatic, Hepa
156x	Gall bladder / ext. biliary	Gbladder, Gbla
157x	Pancreatic	Pancreas, Panc
158x	Peritoneal / retroperitoneal	Periton.
159x	Digestive / peritoneal (general)	DigePeri
160x	Nasal / middle ear	E.N.T.
161x	Laryngeal	Larynx, Lary
162x	Tracheal / lung / bronchial	LungBron, Lung
163x	Pleural	Pleura
164x	Thymus / heart / mediastinum	Mediast.
165x	Respiratory / thoracic (general)	RespThor, ReDi
170x	Bone	Bone
171x	Soft tissue	SoftTiss, Soft
172x	Melanoma	Melanoma, Mela
173x	Skin (general)	Skin
174x	Contralateral breast cancer	ContraBC, Cont
179x	Uterine (general)	Uterine
180x	Cervical	Cervical, Cerv
182x	Endometrial / corpus uteri	Endomet., Endo
183x	Ovarian	Ovarian, Ovar
184x	Genital tract (general)	GenitalT, GenT
188x	Bladder	Bladder, Blad
189x	Renal / urinary system (general)	Urinary, Urol
190x	Ocular	Ocular, Eye
191x	Cerebral	Cerebral, Brai
192x	C.N.S. (general)	C.N.S.
193x	Thyroid	Thyroid, Thyr
194x	Endocrine glands (general)	Endocrin
195x	Ill-defined site	Ill-defd
196x	Lymph Nodes	LymphNod
197x	Respiratory / digestive systems	RespDige
199x	Not stated	?/Unk.
1999	Unknown site	Site?/Unk.
200x	Lymphosarcoma / reticulosarcoma	L/RSarc
201x	Hodgkin's disease	HodgkinD, Hodg
202x	Non-Hodgkin's lymphoma / histiocyt.	N.H.L.
204x	Lymphoid leukaemia	LympLeuk
205x	Myeloid leukaemia	MyelLeuk
207x	Other leukaemia	Leukaem., Leuk
208x	Leukaemia (general)	Leukaem., Leuk
210x	Oral, benign	BenOral
211x	Digestive, benign	BenDiges
212x	Respiratory, benign	BenRespi
225x	Cerebral, benign	BenBrain
226x	Thyroid, benign	BenThyr
237x	Endocrine / nervous, uncertain	EndNerUn, ENU
238x	Uncertain	Uncert
273x	Plasma protein disorder	PlasProt
284x	Aplastic anaemia	Anaemia
289x	Other blood disease	BloodDis

2nd Malig.

Date of second malignancy

55 - 60

DDMMYY

2nd Mal. Date

Distant/unknown recurrence

Value	Description	Abbreviation
1	No	No
2	Distant	Dist
3	Unknown site	Unk.

Dist. Rec

Date of first distant/unk. recurrence

64 - 69

DDMMYY

D-Rec. Date

Prior local recurrence

Value	Description	Abbreviation
1	No	No
2	Yes	Yes
3	Ipsilateral	Ipsi
4	Other locoregional	Othr

Local Rec

Date of prior local recurrence

73 - 78

DDMMYY

L-Rec. Date

State when last traced

Value	Description	Abbreviation
1	Alive	Alive
2	Dead	Dead
3	Lost	Lost
4	Utterly lost	Lost+
5	Alive, ineligible for protocol	A/in.
6	Dead, ineligible for protocol	D/in.
9	Lost, presumed dead	LostD
10	Lost and ineligible	L/in.
11	Utterly lost and ineligible	L+/in.

State

Date died or last traced

82 - 87

DDMMYY

L.F.U.

ICD revision (extra category)

ICDRev

Cause of death (ICD)

90 - 93

ICD

D.ICD

Cause of death (extra category)

95 - 96

Value	Description	Abbreviation
1	Iatrogenic	Iatro
2	Pneumonia	Pneum
3	Lymphatic and haematopoietic	Leuk
4	Other second neoplasm	Neop2
5	Heart	Heart
6	Thrombotic or embolic	ThEmb
7	Cerebrovascular	Cvasc
8	Extraneous cause	Extra
9	Not 1 - 8, 13 - 16 and not breast cancer	NotBC
10	Unspecified non-breast-cancer cause	NotBC
11	Breast cancer or its metastases	BCMet
12	Unascertainable cause	Unkn.
13	Respiratory	Respi
14	Hepatic	Hepat
15	Non-pneumonia infective	Infec
16	Other vascular	OVasc

Death

Name (if given) and comments

98 - end

Name

Missing or unknown items are left blank or set to zero.

BC 1995 data form rubric

[Link to 170 kb JPEG picture of the BC 1995 data form here]

GUARANTEE OF CONFIDENTIALITY OF DATA

ANY INFORMATION PROVIDED OVERLEAF TO THE EBCTCG 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 menopausal status, primary surgery, ER or PR) 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 randomised

Please describe ALL patients EVER randomised, including even lost or withdrawn patients, and ignore all non-randomised patients.

Treatment group allocated

Treatment group number: 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 first allocation.)

Entry age

Age at randomisation.

Menopausal status on entry

0 or blank = not (yet) conveniently available; 1 = pre-, 2 = peri-, 3 = post-menopausal (includes bilateral ovarian ablation before randomisation). Use your own definitions of menopausal status at entry.

Primary surgery

Type of surgery first attempted: 0 or blank = not (yet) conveniently available; 1, 2, 3, 4, 5 = mastectomy (1 = radical; 2 = total (i.e. with axillary clearance); 3 = simple (i.e. without axillary clearance); 4 = partial with axillary clearance; 5 = partial without axillary clearance); 6 = lumpectomy with axillary clearance; 7 = lumpectomy without axillary clearance.

Axilla status on entry

0 or blank = not (yet) conveniently available; 1, 2, 3 = axillary clearance (1 = N0, 2 = N1-3, 3 = N4+); 4, 5 = axillary sample only (4 = N-, 5 = N+); 6, 7 = no sample (6 = clinically N-, 7 = clinically N+).

Est. Rec. on entry

Oestrogen receptor level in units of fmol/mg protein (blank = not (yet) conveniently available).

Prg. Rec. on entry

Progesterone receptor level in units of fmol/mg protein (blank = not (yet) conveniently available).

FOLLOW-UP DATA

Site 2nd malignancy / contralateral breast cancer

Site of second malignancy: please use your own codes and specify them, or use ICD codes.

Approx. date of 2nd malignancy

Give the best estimate you can: see note above on approximate dates.

Distant/unknown recurrence

Any recurrence at distant or unknown site? 1 = no; 2 = distant; 3 = unknown site.

Approx. date of distant/unk. rec.

Give the best estimate you can: see note above on approximate dates.

Prior local

Any prior local recurrence? (Please distinguish ipsilateral breast recurrences from other local recurrences (e.g. by using codes 3 and 4) if the trial included a conservative surgery arm). Please use your own codes and specify them, or use 1 = no local recurrence; 2 = any local recurrence; 3 = ipsilateral breast recurrence; 4 = other locoregional site.

Approx. date of prior local rec.

Give the best estimate you can: see note above on approximate dates.

Dead/other

1 = alive when last traced; 2 = known to be dead; 3 = lost despite extensive inquiries, but alive when last traced.

Date died/last traced

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

Death cause:

(For patients dying without distant recurrence). Please use your own codes and specify them, or use ICD codes.

Guide to coding some death causes in BC 1995 data format

0 No information supplied

(Ask for details if no b.c. recurrence present)

1 Iatrogenic

Postoperative complications of breast surgery
Pulmonary fibrosis post-radiotherapy
Toxicity of protocol treatments

2 Pneumonia

Bronchopneumonia
Pneumonia

3 Lymphatic and haematopoietic malignancy

Classified with ICD-9

4 Other second neoplasm

Classified with ICD-9

5 Heart

Arrhythmias
Arteriosclerosis
Atherosclerosis
Coronary thrombosis
Heart failure
Ischaemic heart disease
Myocardial infarction
Nonspecific heart disease
Pulmonary congestion
Pulmonary oedema
Symptomatic heart disease
Unexplained cardiac arrest
Unexplained cardiac events

6 Thrombotic or embolic

Deep vein thrombosis
Pulmonary embolism
Exclusions:cerebrovascular embolism; coronary thrombosis; myocardial infarction

7 Cerebrovascular

Cerebrovascular accident
Cerebrovascular embolism
Cerebrovascular haemorrhage
Exclusions: cerebral aneurysm; subarachnoid haemorrhage

8 Extraneous cause

Drowning
Falling
Murder
Poisoning (except by protocol treatments)
Suicide
Transportation accident

9 Not 1-8,13-16 and not breast cancer

Diabetes
Miscellaneous
Peritonitis (except septic peritonitis)
Renal failure

10 Not breast cancer

Minimal information provided, or multiple causes (to be re-coded later)
Unknown cause but NED

11 Breast cancer or its metastases

Including other contributory causes

12 Unknown cause

No information available to trialist

13 Respiratory

Asthma
Bronchiectasis
Chronic bronchitis
Chronic obstructive airways disease
Chronic obstructive pulmonary disease
Chronic pulmonary heart disease (not acute)
Cor pulmonale
Emphysema

14 Hepatic

Cirrhosis
Hepatitis
Exclusions: primary or secondary hepatic cancer

15 Non-pneumonia infective

Pericarditis
Septic peritonitis
Exclusions: hepatitis, pneumonia

16 Other vascular

Aortic aneurysm
Cerebral aneurysm
Congenital cardiac anomalies
Rheumatic heart disease
Subarachnoid haemorrhage
Valvular heart disorders
Exclusions: causes 5, 6 and 7

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[End of document, updated to 11 July 2000]