The observed small study effect in the current analysis may also be due to such a true heterogeneity (Higgings, 2008), as a short-term benefit from chemotherapy is more likely in patients with high-performance status for tolerating toxicity of the treatment and such patients are more likely to be included in small, early phase clinical trials in the development of new treatment regimens.
Finally, it should be noted the effect of anaemia was detected in the groups with optimal criteria for response, for example, high performance status and high drug intensity, but with less active regimens or iller patients no effect was seen.
Anaemia was a strong predictor for activity of first-line 5FU-based chemotherapy especially in those groups that showed the best responses, for example high performance status, infusionally treated, higher 5FU dose and those with liver secondaries.
Of aforementioned prognostic factors, high performance status was the most significant parameter in choosing surgical resection for treatment option [ 20, 21].
First, we hypothesized that patients with a high performance status (Karnofsky performance scale [KPS] score > 70) would report lower levels of symptoms and a better QOL than patients with a low performance status (KPS score ≤ 70).
Patients who desired this intervention tended to be younger (odds ratio 0.67 for every ten year increase in age, P < 0.0001) and to have a higher performance status (odds ratio 1.32 for every ten units increase in PPSv2, P = 0.021).
Patients who desired this intervention tended to be younger (odds ratio 0.70 for every ten year increase in age, P = 0.0001), to have a higher performance status (odds ratio 1.47 for every ten units increase in PPSv2, P = 0.0007) and to have a SDM involved in the decision (odds ratios 1.87 and 2.84 for patient/SDM and SDM alone, P = 0.04).
Patients who desired this intervention tended to be younger (odds ratio 0.74 per ten year increase in age, P = 0.002), to have a higher performance status (odds ratio 1.55 for every ten units increase in PPSv2, P = 0.0001) and to have a SDM involved in the decision (odds ratios 1.84 and 2.98 for patient/SDM and SDM alone, P = 0.031).
Inpatients and patients with poorer performance status scored higher on the MSAS-Ch subscale and total scores than outpatients and patients with higher performance status (P < 0.05).
Gogos et al (1998) reported a significantly higher Karnofsky performance status in malnourished patients supplemented for 40 days with 18 g of n-3 PUFA (3 g EPA and 2 g DHA) compared with placebo.
Data missingness was high for performance status and tumor response associations.
