Table 4 The correlations of the criteria grouped by domain. Correlation was reported only if “strong” (i.e., gamma greater than 0.5) and if the respective p-value was less than 0.05. The number specified in the correlation column refers to that of the correlated criteria. The “+” indicates a positive correlation, the “-“a negative correlation. †Criteria 4.6, 4.7 and 4.8 are the criteria added a posteriori of our field studies and they are not currently ranked. For this reason, also correlations are not calculated nor reported (NA)

 6.1 Maintenance costs

6.2,6.3(+)

 6.2 Running costs

6.1(+)

 6.3 Initial cost

6.1(+)

 7.1 Lifetime of MD parts/components

7.2 (+)

 7.2 MD lifetime

7.1(+)

 2.1 Need for consumables

2.2,2.3,2.4,2.5(+)

 2.2 Need for spare parts

2.1,2.3,2.4,2.5(+)

 2.3 Installation requirements

2.1,2.2,2.4,2.5(+)

 2.4 Maintenance complexity

 2.5 Maintenance frequency

2.1,2.2,2.3,2.4(+)

 2.6 Compatible consumables/spare parts

2.4(+)

 3.1 Portability, compactness, robustness

3.2(+)

 3.2 Limiting the number of components/spare parts

3.1(+)

 3.3 Reusability

–

 1.1 End users’ background

1.4(+)

 1.2 Easiness of use

–

 1.3 Training needs

1.4(+)

 1.4 User’s understanding of the technical and clinical impact

1.1(+)

 5.1 Durability of the material

5.2(+)

 5.2 Robustness of the material

5.1 (+)

 4.1 Reliance on power sources

4.2,4.3,4.4(+)

 4.2 Reliance on water distribution

4.1,4.3,4.4(+)

 4.3 Reliance on medical location air

4.1,4.2,4.4,4.5(+)

 4.4 Need for sample preparation

4.1,4.2,4.3,4.5(+)

 4.5 Understanding/stating the dependence of the MD from the medical location characteristics

4.3,4.4(+)

 4.6 Resilience to dusty environments^†

NA

 4.7 Resilience to high-temperature environments^†

 4.8 Resilience to high-humidity environments^†