Table 2 Odds ratios and 95% confidence intervals (CIs) of the association of factors with falciparum infection risk in controls and endemic Burkitt lymphoma in the cases and controls in the combined dataset

Socioeconomic status Q1

Ref

Ref

Ref

Ref

 Q2

0.79 (0.63, 0.99)

0.79 (0.62, 1.01)

1.68 (1.27, 2.22)

2.32 (1.68, 3.20)

 Q3

0.65 (0.52, 0.81)

0.62 (0.48, 0.80)

1.63 (1.24, 2.14)

2.25 (1.58, 3.21)

 Q4

0.44 (0.36, 0.55)

0.45 (0.34, 0.59)

2.13 (1.64, 2.77)

3.25 (2.28, 4.65)

P-trend

< 0.0001

< 0.0001

< 0.0001

< 0.0001

Animals Q1

Ref

Ref

Ref

Ref

 Q2

1.25 (1.02, 1.54)

1.28 (1.03, 1.59)

1.20 (0.94, 1.53)

1.23 (0.93, 1.62)

 Q3

1.37 (1.10, 1.69)

1.41 (1.12, 1.76)

1.02 (0.79, 1.31)

1.14 (0.85, 1.52)

 Q4

1.52 (1.23, 1.87)

1.69 (1.36, 2.11)

1.44 (1.14, 1.82)

1.72 (1.31, 2.25)

P-trend

< 0.0001

< 0.0001

0.01

0.0002

Inpatient malaria Q1

Ref

Ref

Ref

Ref

 Q2

0.77 (0.63, 0.95)

0.75 (0.60, 0.94)

1.94 (1.44, 2.60)

2.09 (1.50, 2.89)

 Q3

0.83 (0.67, 1.02)

0.79 (0.62, 1.01)

2.73 (2.03, 3.68)

2.69 (1.88, 3.84)

 Q4

0.78 (0.63, 0.97)

0.71 (0.56, 0.91)

2.99 (2.24, 3.98)

2.14 (1.51, 3.04)

P-trend

0.05

0.007

< 0.0001

< 0.0001

Outpatient malaria Q1

Ref

Ref

Ref

Ref

 Q2

1.01 (0.82, 1.25)

0.90 (0.72, 1.12)

1.40 (1.08, 1.81)

1.24 (0.92, 1.66)

 Q3

1.17 (0.95, 1.45)

1.05 (0.84, 1.31)

1.16 (0.89, 1.51)

1.16 (0.86, 1.56)

 Q4

1.01 (0.82, 1.24)

1.08 (0.85, 1.36)

1.82 (1.43, 2.32)

1.75 (1.31, 2.33)

P-trend

0.60

0.20

< 0.0001

0.0004

Non-specific febrile symptoms Q1

Ref

Ref

Ref

Ref

 Q2

1.44 (1.16, 1.79)

1.35 (1.08, 1.71)

0.81 (0.60, 1.09)

1.26 (0.91, 1.75)

 Q3

1.35 (1.09, 1.67)

1.29 (1.01, 1.64)

0.75 (0.55, 1.03)

1.53 (1.08, 2.17)

 Q4

1.27 (1.03, 1.58)

1.40 (1.09, 1.78)

3.49 (2.75, 4.43)

7.30 (5.45, 9.79)

P-trend

0.06

0.009

< 0.0001

< 0.0001

Home environment Q1

Ref

Ref

Ref

Ref

 Q2

1.29 (1.05, 1.59)

1.20 (0.97, 1.50)

0.96 (0.74, 1.23)

1.27 (0.95, 1.70)

 Q3

1.22 (0.98, 1.52)

1.14 (0.91, 1.44)

1.19 (0.94, 1.52)

1.61 (1.21, 2.13)

 Q4

1.38 (1.12, 1.70)

1.38 (1.10, 1.73)

1.29 (1.01, 1.63)

1.83 (1.38, 2.44)

P-trend

0.005

0.008

0.01

0.0003

 TFM or RDT results

–

–

 Negative on both tests

–

–

Ref

Ref

 TFM or RDT positive

–

–

0.43 (0.40, 0.47)

0.46 (0.37, 0.56)

Malaria infection

Negative on both tests

–

–

Ref

Ref

Recent (only RDT positive)

–

–

0.44 (0.38, 0.50)

0.44 (0.29, 0.65)

Current (TFM positive)

–

–

0.47 (0.43, 0.51)

0.51 (0.39, 0.66)

P-trend

< 0.0001

< 0.0001