**5. Is it really necessary to determine risk in QRM?**

This is not the kind of stupid question that, at first sight, might seem. And in fact this is not a question, but two. The first one might be related to the fact that in everyday's life we somehow tend to mix-up hazard and risk. As the latter is the consequence of the former, we tend to consider both practically as synonymous. The second one comes out because of the fact that identification of hazards is a prerequisite for the determination of their risk, and risk allows for an assessment of hazard. Thus, why to limit ourselves to something of "low level" like hazard when we can get something "better" like risk? Unfortunately this is not correct. By definition, to determine risk we have to start by knowing the probability of occurrence of the hazard. And this is often very difficult and in the end it turns to be just an inference. Then, we should know the seriousness of the harm and, although this is usually clearer, it is neither an easy task and often requires some degree of imagination. Consequently, in many cases, risk is not more than an estimation, that has to be improved along the time as more experience is collected. The case might be that hazard, usually a concrete thing, is substituted by risk, an estimated value and this can hardly be something better.

In practice, our first aim should be to determine hazard and then, only if there is an objective possibility of estimating risk, do it. Speaking in general terms the evolution should be hazard detection > qualitative risk estimation > quantitative risk estimation. In projects or new processes we would move towards the left (hazard), whereas as we gain process knowledge we might move towards the right (risk).

Summarizing, although we talk about QRM it is perfectly acceptable just to determine hazard and manage it in terms of making the appearance of harm an unluckily event by applying corrective measures. It is better to limit a QRA to the hazards that trying to estimate risk without having enough information for doing it.

Quality Risk Analysis: Value for Money in the Pharmaceutical Industry 403

**DETECTION** 

The failure /accident **will very likely not be detected** 

The failure /accident **might be detected** 

The failure /accident **will very likely be detected** 

Another point that needs to be discussed, when using quantitative evaluation, is the relation between these levels. Beside the normal series of values (1, 2, 3, etc.), we might use other with wider gaps between the levels, either regular (e. g., 1, 3, 5, 7) or even irregular (e. g., 1, 3, 7, 12). These last cases would give more weight to the higher levels, thus increasing the sensation of higher risk. It is not necessary to insist on the fact that any type of characterization of the levels is acceptable, provided that it is clearly defined and indicated and that it is not used to take false conclusions regarding higher evaluations of

**Evaluation PROBABILITY SEVERITY DIFFICULTY OF** 

**Evaluation PROBABILITY SEVERITY DIFFICULTY OF DETECTION Very high** Always Catastrophic It cannot be detected

**Very low** Non observable Insignificant It can be detected instantaneously

**High** Often (probable) Critical It can only be detected when the process is already finished **Medium** Sometimes Serious It can be detected during one of the stages of the process **Low** Rare (improbable) Minor It can be detected during the stage in process

An important inconvenient of the qualitative evaluation of the factors appears when determining risk. Everybody would agree that low x medium x high = medium, but the score of low x low x high is not so evident (medium?). And this becomes even more unclear

This is however less important that it might seem at first sight. As we have seen above, risk estimation, and particularly the qualitative one, is likely to be more a rough approximation than a very exact value. Thus, adding some more roughness should not be considered critical. In any case, this inconvenient can be overcome by using a complementary table

The consequences of the failure /accident are **important** 

The consequences of the failure /accident are **moderate** 

The consequences of the failure /accident are **low** 

risk.

**7.1. Qualitative evaluation** 

**High** The failure /accident occurs

**Medium** The failure /accident occurs

**Low** The failure /accident occurs

**frequently** 

**periodically** 

**rarely** 

**Table 12.** Example of qualitative evaluation in three levels

**Table 13.** Example of qualitative evaluation in five levels

which would provide a homogeneous estimation.

if we consider more than three levels.

For instance in three levels:

More than three levels:
